12557981 has 2 divisors, whose sum is σ = 12557982. Its totient is φ = 12557980.

The previous prime is 12557969. The next prime is 12558017. The reversal of 12557981 is 18975521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11792356 + 765625 = 3434^2 + 875^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12557981 is a prime.

It is a super-2 number, since 2×12557981² = 315405773592722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12554981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6278990 + 6278991.

It is an arithmetic number, because the mean of its divisors is an integer number (6278991).

Almost surely, 2^12557981 is an apocalyptic number.

It is an amenable number.

12557981 is a deficient number, since it is larger than the sum of its proper divisors (1).

12557981 is an equidigital number, since it uses as much as digits as its factorization.

12557981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25200, while the sum is 38.

The square root of 12557981 is about 3543.7241709817. The cubic root of 12557981 is about 232.4377202439.

The spelling of 12557981 in words is "twelve million, five hundred fifty-seven thousand, nine hundred eighty-one".