669985660 has 24 divisors (see below), whose sum is σ = 1413288576. Its totient is φ = 266790720.

The previous prime is 669985601. The next prime is 669985697. The reversal of 669985660 is 66589966.

It is a congruent number.

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, 70651 + ... + 79570.

It is an arithmetic number, because the mean of its divisors is an integer number (58887024).

Almost surely, 2^669985660 is an apocalyptic number.

It is an amenable number.

669985660 is an abundant number, since it is smaller than the sum of its proper divisors (743302916).

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

669985660 is a wasteful number, since it uses less digits than its factorization.

669985660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150453 (or 150451 counting only the distinct ones).

The product of its (nonzero) digits is 4199040, while the sum is 55.

The square root of 669985660 is about 25884.0812083412. The cubic root of 669985660 is about 875.0277694588.

The spelling of 669985660 in words is "six hundred sixty-nine million, nine hundred eighty-five thousand, six hundred sixty".