12991256 has 8 divisors (see below), whose sum is σ = 24358620. Its totient is φ = 6495624.

The previous prime is 12991249. The next prime is 12991261. The reversal of 12991256 is 65219921.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

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 as a sum of consecutive naturals, namely, 811946 + ... + 811961.

Almost surely, 2^12991256 is an apocalyptic number.

It is an amenable number.

12991256 is a deficient number, since it is larger than the sum of its proper divisors (11367364).

12991256 is a wasteful number, since it uses less digits than its factorization.

12991256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1623913 (or 1623909 counting only the distinct ones).

The product of its digits is 9720, while the sum is 35.

The square root of 12991256 is about 3604.3384968674. The cubic root of 12991256 is about 235.0807388185.

The spelling of 12991256 in words is "twelve million, nine hundred ninety-one thousand, two hundred fifty-six".