25643624140 has 72 divisors (see below), whose sum is σ = 56676085200. Its totient is φ = 9745025664.

The previous prime is 25643624137. The next prime is 25643624159. The reversal of 25643624140 is 4142634652.

It is a self number, because there is not a number n which added to its sum of digits gives 25643624140.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1568287 + ... + 1584553.

It is an arithmetic number, because the mean of its divisors is an integer number (787167850).

Almost surely, 2^25643624140 is an apocalyptic number.

25643624140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25643624140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28338042600).

25643624140 is an abundant number, since it is smaller than the sum of its proper divisors (31032461060).

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

25643624140 is a wasteful number, since it uses less digits than its factorization.

25643624140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16471 (or 16446 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 37.

The spelling of 25643624140 in words is "twenty-five billion, six hundred forty-three million, six hundred twenty-four thousand, one hundred forty".