25393616640 has 864 divisors, whose sum is σ = 106066920960. Its totient is φ = 5697257472.

The previous prime is 25393616639. The next prime is 25393616671. The reversal of 25393616640 is 4661639352.

25393616640 is a `hidden beast` number, since 25 + 3 + 9 + 3 + 616 + 6 + 4 + 0 = 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 (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 232968906 + ... + 232969014.

It is an arithmetic number, because the mean of its divisors is an integer number (122762640).

Almost surely, 2^25393616640 is an apocalyptic number.

25393616640 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 25393616640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53033460480).

25393616640 is an abundant number, since it is smaller than the sum of its proper divisors (80673304320).

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

25393616640 is a wasteful number, since it uses less digits than its factorization.

25393616640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259 (or 233 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 45.

The spelling of 25393616640 in words is "twenty-five billion, three hundred ninety-three million, six hundred sixteen thousand, six hundred forty".