25643820474 has 24 divisors (see below), whose sum is σ = 56853743232. Its totient is φ = 8349150600.

The previous prime is 25643820443. The next prime is 25643820511. The reversal of 25643820474 is 47402834652.

It is a happy number.

25643820474 is a `hidden beast` number, since 2 + 5 + 6 + 438 + 204 + 7 + 4 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16565002 + ... + 16566549.

It is an arithmetic number, because the mean of its divisors is an integer number (2368905968).

Almost surely, 2^25643820474 is an apocalyptic number.

25643820474 is an abundant number, since it is smaller than the sum of its proper divisors (31209922758).

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

25643820474 is a wasteful number, since it uses less digits than its factorization.

25643820474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33131602 (or 33131599 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 45.

The spelling of 25643820474 in words is "twenty-five billion, six hundred forty-three million, eight hundred twenty thousand, four hundred seventy-four".