25689311957 has 2 divisors, whose sum is σ = 25689311958. Its totient is φ = 25689311956.

The previous prime is 25689311951. The next prime is 25689312001. The reversal of 25689311957 is 75911398652.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16710991441 + 8978320516 = 129271^2 + 94754^2 .

It is a cyclic number.

It is not a de Polignac number, because 25689311957 - 2¹⁶ = 25689246421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25689311951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12844655978 + 12844655979.

It is an arithmetic number, because the mean of its divisors is an integer number (12844655979).

Almost surely, 2^25689311957 is an apocalyptic number.

It is an amenable number.

25689311957 is a deficient number, since it is larger than the sum of its proper divisors (1).

25689311957 is an equidigital number, since it uses as much as digits as its factorization.

25689311957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4082400, while the sum is 56.

The spelling of 25689311957 in words is "twenty-five billion, six hundred eighty-nine million, three hundred eleven thousand, nine hundred fifty-seven".