25408986021 has 6 divisors (see below), whose sum is σ = 36701868710. Its totient is φ = 16939324008.

The previous prime is 25408985989. The next prime is 25408986023. The reversal of 25408986021 is 12068980452.

25408986021 is a `hidden beast` number, since 2 + 540 + 8 + 9 + 86 + 0 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 25125737121 + 283248900 = 158511^2 + 16830^2 .

It is not a de Polignac number, because 25408986021 - 2⁵ = 25408985989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25408986023) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1411610326 + ... + 1411610343.

Almost surely, 2^25408986021 is an apocalyptic number.

It is an amenable number.

25408986021 is a deficient number, since it is larger than the sum of its proper divisors (11292882689).

25408986021 is a wasteful number, since it uses less digits than its factorization.

25408986021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2823220675 (or 2823220672 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 25408986021 in words is "twenty-five billion, four hundred eight million, nine hundred eighty-six thousand, twenty-one".