664908531 has 16 divisors (see below), whose sum is σ = 1014682368. Its totient is φ = 379389600.

The previous prime is 664908523. The next prime is 664908547. The reversal of 664908531 is 135809466.

It is not a de Polignac number, because 664908531 - 2³ = 664908523 is a prime.

It is a super-2 number, since 2×664908531² = 884206709193155922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (664908511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8400 + ... + 37421.

It is an arithmetic number, because the mean of its divisors is an integer number (63417648).

Almost surely, 2^664908531 is an apocalyptic number.

664908531 is a deficient number, since it is larger than the sum of its proper divisors (349773837).

664908531 is a wasteful number, since it uses less digits than its factorization.

664908531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46522.

The product of its (nonzero) digits is 155520, while the sum is 42.

The square root of 664908531 is about 25785.8203476252. The cubic root of 664908531 is about 872.8118521909.

The spelling of 664908531 in words is "six hundred sixty-four million, nine hundred eight thousand, five hundred thirty-one".