25665964128 has 96 divisors (see below), whose sum is σ = 85553233920. Its totient is φ = 7333130880.

The previous prime is 25665964117. The next prime is 25665964139. The reversal of 25665964128 is 82146956652.

25665964128 is a `hidden beast` number, since 2 + 5 + 6 + 6 + 596 + 41 + 2 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (25665964117) and next prime (25665964139).

It is a tau number, because it is divible by the number of its divisors (96).

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 15 ways as a sum of consecutive naturals, for example, 2115808 + ... + 2127903.

It is an arithmetic number, because the mean of its divisors is an integer number (891179520).

Almost surely, 2^25665964128 is an apocalyptic number.

25665964128 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

25665964128 is an abundant number, since it is smaller than the sum of its proper divisors (59887269792).

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

25665964128 is a wasteful number, since it uses less digits than its factorization.

25665964128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4243737 (or 4243723 counting only the distinct ones).

The product of its digits is 6220800, while the sum is 54.

The spelling of 25665964128 in words is "twenty-five billion, six hundred sixty-five million, nine hundred sixty-four thousand, one hundred twenty-eight".