25797277440 has 864 divisors, whose sum is σ = 104391168000. Its totient is φ = 6021734400.

The previous prime is 25797277357. The next prime is 25797277481. The reversal of 25797277440 is 4477279752.

25797277440 is a `hidden beast` number, since 2 + 579 + 7 + 27 + 7 + 4 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 129634461 + ... + 129634659.

Almost surely, 2^25797277440 is an apocalyptic number.

25797277440 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 25797277440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52195584000).

25797277440 is an abundant number, since it is smaller than the sum of its proper divisors (78593890560).

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

25797277440 is a wasteful number, since it uses less digits than its factorization.

25797277440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282 (or 251 counting only the distinct ones).

The product of its (nonzero) digits is 6914880, while the sum is 54.

The spelling of 25797277440 in words is "twenty-five billion, seven hundred ninety-seven million, two hundred seventy-seven thousand, four hundred forty".