12391312 has 30 divisors (see below), whose sum is σ = 24575622. Its totient is φ = 6051456.

The previous prime is 12391303. The next prime is 12391321. The reversal of 12391312 is 21319321.

It is an interprime number because it is at equal distance from previous prime (12391303) and next prime (12391321).

It can be written as a sum of positive squares in only one way, i.e., 10863616 + 1527696 = 3296^2 + 1236^2 .

It is a super-2 number, since 2×12391312² = 307089226162688, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 120253 + ... + 120355.

Almost surely, 2^12391312 is an apocalyptic number.

It is an amenable number.

12391312 is a deficient number, since it is larger than the sum of its proper divisors (12184310).

12391312 is an equidigital number, since it uses as much as digits as its factorization.

12391312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287 (or 178 counting only the distinct ones).

The product of its digits is 324, while the sum is 22.

The square root of 12391312 is about 3520.1295430708. The cubic root of 12391312 is about 231.4048359687.

The spelling of 12391312 in words is "twelve million, three hundred ninety-one thousand, three hundred twelve".