25630669681 has 2 divisors, whose sum is σ = 25630669682. Its totient is φ = 25630669680.

The previous prime is 25630669651. The next prime is 25630669733. The reversal of 25630669681 is 18696603652.

It is an a-pointer prime, because the next prime (25630669733) can be obtained adding 25630669681 to its sum of digits (52).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18059059456 + 7571610225 = 134384^2 + 87015^2 .

It is a cyclic number.

It is not a de Polignac number, because 25630669681 - 2²³ = 25622281073 is a prime.

It is a super-2 number, since 2×25630669681² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25630669651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12815334840 + 12815334841.

It is an arithmetic number, because the mean of its divisors is an integer number (12815334841).

Almost surely, 2^25630669681 is an apocalyptic number.

It is an amenable number.

25630669681 is a deficient number, since it is larger than the sum of its proper divisors (1).

25630669681 is an equidigital number, since it uses as much as digits as its factorization.

25630669681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2799360, while the sum is 52.

The spelling of 25630669681 in words is "twenty-five billion, six hundred thirty million, six hundred sixty-nine thousand, six hundred eighty-one".