664516858 has 4 divisors (see below), whose sum is σ = 996775290. Its totient is φ = 332258428.

The previous prime is 664516843. The next prime is 664516871. The reversal of 664516858 is 858615466.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 632673409 + 31843449 = 25153^2 + 5643^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166129213 + ... + 166129216.

Almost surely, 2^664516858 is an apocalyptic number.

664516858 is a deficient number, since it is larger than the sum of its proper divisors (332258432).

664516858 is a wasteful number, since it uses less digits than its factorization.

664516858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332258431.

The product of its digits is 1382400, while the sum is 49.

The square root of 664516858 is about 25778.2244927768. The cubic root of 664516858 is about 872.6404381453.

The spelling of 664516858 in words is "six hundred sixty-four million, five hundred sixteen thousand, eight hundred fifty-eight".