25544579640 has 64 divisors (see below), whose sum is σ = 80667100800. Its totient is φ = 6453366912.

The previous prime is 25544579633. The next prime is 25544579663. The reversal of 25544579640 is 4697544552.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5599602 + ... + 5604161.

It is an arithmetic number, because the mean of its divisors is an integer number (1260423450).

Almost surely, 2^25544579640 is an apocalyptic number.

25544579640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25544579640 is an abundant number, since it is smaller than the sum of its proper divisors (55122521160).

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

25544579640 is a wasteful number, since it uses less digits than its factorization.

25544579640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11203796 (or 11203792 counting only the distinct ones).

The product of its (nonzero) digits is 6048000, while the sum is 51.

The spelling of 25544579640 in words is "twenty-five billion, five hundred forty-four million, five hundred seventy-nine thousand, six hundred forty".