664525431 has 8 divisors (see below), whose sum is σ = 984482160. Its totient is φ = 443016936.

The previous prime is 664525387. The next prime is 664525471. The reversal of 664525431 is 134525466.

664525431 is a `hidden beast` number, since 6 + 64 + 52 + 543 + 1 = 666.

It is not a de Polignac number, because 664525431 - 2⁹ = 664524919 is a prime.

It is a super-2 number, since 2×664525431² = 883188096891471522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664525471) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12306000 + ... + 12306053.

It is an arithmetic number, because the mean of its divisors is an integer number (123060270).

Almost surely, 2^664525431 is an apocalyptic number.

664525431 is a deficient number, since it is larger than the sum of its proper divisors (319956729).

664525431 is a wasteful number, since it uses less digits than its factorization.

664525431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24612062 (or 24612056 counting only the distinct ones).

The product of its digits is 86400, while the sum is 36.

The square root of 664525431 is about 25778.3907759969. The cubic root of 664525431 is about 872.6441908037.

The spelling of 664525431 in words is "six hundred sixty-four million, five hundred twenty-five thousand, four hundred thirty-one".