660644012 has 24 divisors (see below), whose sum is σ = 1366851360. Its totient is φ = 273369600.

The previous prime is 660644009. The next prime is 660644077. The reversal of 660644012 is 210446066.

It is a super-2 number, since 2×660644012² = 872901021182912288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 405989 + ... + 407612.

It is an arithmetic number, because the mean of its divisors is an integer number (56952140).

Almost surely, 2^660644012 is an apocalyptic number.

It is an amenable number.

660644012 is an abundant number, since it is smaller than the sum of its proper divisors (706207348).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

660644012 is a wasteful number, since it uses less digits than its factorization.

660644012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 813641 (or 813639 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 660644012 is about 25702.9961677622. The cubic root of 660644012 is about 870.9418662975.

The spelling of 660644012 in words is "six hundred sixty million, six hundred forty-four thousand, twelve".