25961734656 has 640 divisors, whose sum is σ = 94373959680. Its totient is φ = 6934118400.

The previous prime is 25961734621. The next prime is 25961734709. The reversal of 25961734656 is 65643716952.

25961734656 is a `hidden beast` number, since 2 + 5 + 9 + 6 + 173 + 465 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 45466851 + ... + 45467421.

It is an arithmetic number, because the mean of its divisors is an integer number (147459312).

Almost surely, 2^25961734656 is an apocalyptic number.

25961734656 is a gapful number since it is divisible by the number (26) 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 25961734656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47186979840).

25961734656 is an abundant number, since it is smaller than the sum of its proper divisors (68412225024).

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

25961734656 is a wasteful number, since it uses less digits than its factorization.

25961734656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 645 (or 623 counting only the distinct ones).

The product of its digits is 8164800, while the sum is 54.

The spelling of 25961734656 in words is "twenty-five billion, nine hundred sixty-one million, seven hundred thirty-four thousand, six hundred fifty-six".