25688731 has 2 divisors, whose sum is σ = 25688732. Its totient is φ = 25688730.

The previous prime is 25688701. The next prime is 25688737. The reversal of 25688731 is 13788652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25688731 - 2⁵ = 25688699 is a prime.

It is a super-2 number, since 2×25688731² = 1319821800780722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25688737) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12844365 + 12844366.

It is an arithmetic number, because the mean of its divisors is an integer number (12844366).

Almost surely, 2^25688731 is an apocalyptic number.

25688731 is a deficient number, since it is larger than the sum of its proper divisors (1).

25688731 is an equidigital number, since it uses as much as digits as its factorization.

25688731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80640, while the sum is 40.

The square root of 25688731 is about 5068.4051732276. The cubic root of 25688731 is about 295.0626353643.

The spelling of 25688731 in words is "twenty-five million, six hundred eighty-eight thousand, seven hundred thirty-one".