25640642523 has 32 divisors (see below), whose sum is σ = 35835739200. Its totient is φ = 16286054400.

The previous prime is 25640642483. The next prime is 25640642549. The reversal of 25640642523 is 32524604652.

It is not a de Polignac number, because 25640642523 - 2¹⁶ = 25640576987 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25640642123) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4185903 + ... + 4192023.

It is an arithmetic number, because the mean of its divisors is an integer number (1119866850).

Almost surely, 2^25640642523 is an apocalyptic number.

25640642523 is a deficient number, since it is larger than the sum of its proper divisors (10195096677).

25640642523 is a wasteful number, since it uses less digits than its factorization.

25640642523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6783.

The product of its (nonzero) digits is 345600, while the sum is 39.

The spelling of 25640642523 in words is "twenty-five billion, six hundred forty million, six hundred forty-two thousand, five hundred twenty-three".