15625969 has 2 divisors, whose sum is σ = 15625970. Its totient is φ = 15625968.

The previous prime is 15625931. The next prime is 15626003. The reversal of 15625969 is 96952651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13838400 + 1787569 = 3720^2 + 1337^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15625969 is a prime.

It is a super-2 number, since 2×15625969² = 488341814377922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (15625919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7812984 + 7812985.

It is an arithmetic number, because the mean of its divisors is an integer number (7812985).

Almost surely, 2^15625969 is an apocalyptic number.

It is an amenable number.

15625969 is a deficient number, since it is larger than the sum of its proper divisors (1).

15625969 is an equidigital number, since it uses as much as digits as its factorization.

15625969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145800, while the sum is 43.

The square root of 15625969 is about 3952.9696431923. The cubic root of 15625969 is about 250.0051678932.

The spelling of 15625969 in words is "fifteen million, six hundred twenty-five thousand, nine hundred sixty-nine".