25663657 has 2 divisors, whose sum is σ = 25663658. Its totient is φ = 25663656.

The previous prime is 25663621. The next prime is 25663667. The reversal of 25663657 is 75636652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25110121 + 553536 = 5011^2 + 744^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25663657 is a prime.

It is a super-2 number, since 2×25663657² = 1317246581227298, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25663667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12831828 + 12831829.

It is an arithmetic number, because the mean of its divisors is an integer number (12831829).

Almost surely, 2^25663657 is an apocalyptic number.

It is an amenable number.

25663657 is a deficient number, since it is larger than the sum of its proper divisors (1).

25663657 is an equidigital number, since it uses as much as digits as its factorization.

25663657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 226800, while the sum is 40.

The square root of 25663657 is about 5065.9310101895. The cubic root of 25663657 is about 294.9666035161.

The spelling of 25663657 in words is "twenty-five million, six hundred sixty-three thousand, six hundred fifty-seven".