12811491 has 72 divisors (see below), whose sum is σ = 24897600. Its totient is φ = 6259680.

The previous prime is 12811481. The next prime is 12811493. The reversal of 12811491 is 19411821.

It is not a de Polignac number, because 12811491 - 2⁵ = 12811459 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12811493) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 92100 + ... + 92238.

It is an arithmetic number, because the mean of its divisors is an integer number (345800).

Almost surely, 2^12811491 is an apocalyptic number.

12811491 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12811491 is a deficient number, since it is larger than the sum of its proper divisors (12086109).

12811491 is a wasteful number, since it uses less digits than its factorization.

12811491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189 (or 179 counting only the distinct ones).

The product of its digits is 576, while the sum is 27.

The square root of 12811491 is about 3579.3143198104. The cubic root of 12811491 is about 233.9913978867.

It can be divided in two parts, 1281 and 1491, that added together give a palindrome (2772).

The spelling of 12811491 in words is "twelve million, eight hundred eleven thousand, four hundred ninety-one".