25640044960 has 36 divisors (see below), whose sum is σ = 60579391698. Its totient is φ = 10255207808.

The previous prime is 25640044951. The next prime is 25640044973. The reversal of 25640044960 is 6944004652.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 23076040464 + 2564004496 = 151908^2 + 50636^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2019111 + ... + 2031769.

Almost surely, 2^25640044960 is an apocalyptic number.

25640044960 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25640044960 is an abundant number, since it is smaller than the sum of its proper divisors (34939346738).

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

25640044960 is an frugal number, since it uses more digits than its factorization.

25640044960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25333 (or 12666 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 40.

Multiplying 25640044960 by its sum of digits (40), we get a square (1025601798400 = 1012720²).

25640044960 divided by its sum of digits (40) gives a square (641001124 = 25318²).

The spelling of 25640044960 in words is "twenty-five billion, six hundred forty million, forty-four thousand, nine hundred sixty".