25561218696 has 32 divisors (see below), whose sum is σ = 68818666560. Its totient is φ = 7864990272.

The previous prime is 25561218689. The next prime is 25561218701. The reversal of 25561218696 is 69681216552.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40963180 + ... + 40963803.

It is an arithmetic number, because the mean of its divisors is an integer number (2150583330).

Almost surely, 2^25561218696 is an apocalyptic number.

25561218696 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

25561218696 is an abundant number, since it is smaller than the sum of its proper divisors (43257447864).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25561218696 is a wasteful number, since it uses less digits than its factorization.

25561218696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81927005 (or 81927001 counting only the distinct ones).

The product of its digits is 1555200, while the sum is 51.

The spelling of 25561218696 in words is "twenty-five billion, five hundred sixty-one million, two hundred eighteen thousand, six hundred ninety-six".