660405974 has 4 divisors (see below), whose sum is σ = 990608964. Its totient is φ = 330202986.

The previous prime is 660405959. The next prime is 660406031. The reversal of 660405974 is 479504066.

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

It is a super-2 number, since 2×660405974² = 872272100989777352, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165101492 + ... + 165101495.

It is an arithmetic number, because the mean of its divisors is an integer number (247652241).

Almost surely, 2^660405974 is an apocalyptic number.

660405974 is a deficient number, since it is larger than the sum of its proper divisors (330202990).

660405974 is a wasteful number, since it uses less digits than its factorization.

660405974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330202989.

The product of its (nonzero) digits is 181440, while the sum is 41.

The square root of 660405974 is about 25698.3652009228. The cubic root of 660405974 is about 870.8372501145.

The spelling of 660405974 in words is "six hundred sixty million, four hundred five thousand, nine hundred seventy-four".