25218758664 has 768 divisors, whose sum is σ = 88504565760. Its totient is φ = 6386688000.

The previous prime is 25218758657. The next prime is 25218758699. The reversal of 25218758664 is 46685781252.

25218758664 is a `hidden beast` number, since 2 + 52 + 1 + 8 + 7 + 586 + 6 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 25218758664.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 355193749 + ... + 355193819.

It is an arithmetic number, because the mean of its divisors is an integer number (115240320).

Almost surely, 2^25218758664 is an apocalyptic number.

25218758664 is a gapful number since it is divisible by the number (24) 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 25218758664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44252282880).

25218758664 is an abundant number, since it is smaller than the sum of its proper divisors (63285807096).

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

25218758664 is a wasteful number, since it uses less digits than its factorization.

25218758664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202 (or 195 counting only the distinct ones).

The product of its digits is 6451200, while the sum is 54.

The spelling of 25218758664 in words is "twenty-five billion, two hundred eighteen million, seven hundred fifty-eight thousand, six hundred sixty-four".