665973660 has 96 divisors (see below), whose sum is σ = 2083947264. Its totient is φ = 157504000.

The previous prime is 665973647. The next prime is 665973677. The reversal of 665973660 is 66379566.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14755 + ... + 39365.

It is an arithmetic number, because the mean of its divisors is an integer number (21707784).

Almost surely, 2^665973660 is an apocalyptic number.

665973660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665973660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1041973632).

665973660 is an abundant number, since it is smaller than the sum of its proper divisors (1417973604).

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

665973660 is a wasteful number, since it uses less digits than its factorization.

665973660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24675 (or 24673 counting only the distinct ones).

The product of its (nonzero) digits is 1224720, while the sum is 48.

The square root of 665973660 is about 25806.4654689479. The cubic root of 665973660 is about 873.2776612467.

The spelling of 665973660 in words is "six hundred sixty-five million, nine hundred seventy-three thousand, six hundred sixty".