665660478884 has 6 divisors (see below), whose sum is σ = 1164905838054. Its totient is φ = 332830239440.

The previous prime is 665660478803. The next prime is 665660478949. The reversal of 665660478884 is 488874066566.

It can be written as a sum of positive squares in only one way, i.e., 452888620900 + 212771857984 = 672970^2 + 461272^2 .

It is a super-3 number, since 3×665660478884³ (a number of 36 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83207559857 + ... + 83207559864.

It is an arithmetic number, because the mean of its divisors is an integer number (194150973009).

Almost surely, 2^665660478884 is an apocalyptic number.

It is an amenable number.

665660478884 is a deficient number, since it is larger than the sum of its proper divisors (499245359170).

665660478884 is a wasteful number, since it uses less digits than its factorization.

665660478884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166415119725 (or 166415119723 counting only the distinct ones).

The product of its (nonzero) digits is 371589120, while the sum is 68.

The spelling of 665660478884 in words is "six hundred sixty-five billion, six hundred sixty million, four hundred seventy-eight thousand, eight hundred eighty-four".