25697616840 has 576 divisors, whose sum is σ = 104484556800. Its totient is φ = 5441458176.

The previous prime is 25697616817. The next prime is 25697616859. The reversal of 25697616840 is 4861679652.

25697616840 is a `hidden beast` number, since 2 + 569 + 76 + 1 + 6 + 8 + 4 + 0 = 666.

It is a super-2 number, since 2×25697616840² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 20091321 + ... + 20092599.

It is an arithmetic number, because the mean of its divisors is an integer number (181396800).

Almost surely, 2^25697616840 is an apocalyptic number.

25697616840 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 25697616840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52242278400).

25697616840 is an abundant number, since it is smaller than the sum of its proper divisors (78786939960).

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

25697616840 is a wasteful number, since it uses less digits than its factorization.

25697616840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1394 (or 1380 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 54.

The spelling of 25697616840 in words is "twenty-five billion, six hundred ninety-seven million, six hundred sixteen thousand, eight hundred forty".