668644983 has 64 divisors (see below), whose sum is σ = 1091174400. Its totient is φ = 403302240.

The previous prime is 668644943. The next prime is 668645009. The reversal of 668644983 is 389446866.

It is not a de Polignac number, because 668644983 - 2⁸ = 668644727 is a prime.

It is a super-2 number, since 2×668644983² = 894172226582140578, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668644943) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 904428 + ... + 905166.

It is an arithmetic number, because the mean of its divisors is an integer number (17049600).

Almost surely, 2^668644983 is an apocalyptic number.

668644983 is a deficient number, since it is larger than the sum of its proper divisors (422529417).

668644983 is a wasteful number, since it uses less digits than its factorization.

668644983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 849 (or 843 counting only the distinct ones).

The product of its digits is 5971968, while the sum is 54.

The square root of 668644983 is about 25858.1705269340. The cubic root of 668644983 is about 874.4437206529.

The spelling of 668644983 in words is "six hundred sixty-eight million, six hundred forty-four thousand, nine hundred eighty-three".