minor fix in account and account utils (#14432)

diff --git a/erpnext/accounts/doctype/account/account.py b/erpnext/accounts/doctype/account/account.py
index dcdf02c..3e1da66 100644
--- a/erpnext/accounts/doctype/account/account.py
+++ b/erpnext/accounts/doctype/account/account.py
@@ -20,14 +20,16 @@
 			self.set_onload("can_freeze_account", True)
 
 	def autoname(self):
-		self.name = get_account_autoname(self.account_number, self.account_name, self.company)
+		from erpnext.accounts.utils import get_doc_name_autoname
+		self.name = get_doc_name_autoname(self.account_number, self.account_name, None, self.company)
 
 	def validate(self):
+		from erpnext.accounts.utils import validate_field_number
 		if frappe.local.flags.allow_unverified_charts:
 			return
 		self.validate_parent()
 		self.validate_root_details()
-		validate_account_number(self.name, self.account_number, self.company)
+		validate_field_number("Account", self.name, self.account_number, self.company, "account_number")
 		self.validate_group_or_ledger()
 		self.set_root_and_report_type()
 		self.validate_mandatory()
diff --git a/erpnext/accounts/doctype/cost_center/cost_center.py b/erpnext/accounts/doctype/cost_center/cost_center.py
index 1200902..88d8499 100644
--- a/erpnext/accounts/doctype/cost_center/cost_center.py
+++ b/erpnext/accounts/doctype/cost_center/cost_center.py
@@ -13,7 +13,6 @@
 	def autoname(self):
 		self.name = self.cost_center_name.strip() + ' - ' + \
 			frappe.db.get_value("Company", self.company, "abbr")
-			
 
 	def validate(self):
 		self.validate_mandatory()
diff --git a/erpnext/accounts/utils.py b/erpnext/accounts/utils.py
index b1c1972..1ff0986 100644
--- a/erpnext/accounts/utils.py
+++ b/erpnext/accounts/utils.py
@@ -805,11 +805,12 @@
 
 def get_doc_name_autoname(field_value, doc_title, name, company):
 	''' append title with prefix as number and suffix as company's abbreviation separated by '-' '''
-	if company:
+	if name:
 		name_split=name.split("-")
 		parts = [doc_title.strip(), name_split[len(name_split)-1].strip()]
 	else:
-		parts = [doc_title.strip()]
+		abbr = frappe.db.get_value("Company", company, ["abbr"], as_dict=True)
+		parts = [doc_title.strip(), abbr.abbr]
 	if cstr(field_value).strip():
 		parts.insert(0, cstr(field_value).strip())
 	return ' - '.join(parts)