665974320 has 480 divisors, whose sum is σ = 2564835840. Its totient is φ = 141926400.

The previous prime is 665974319. The next prime is 665974343. The reversal of 665974320 is 23479566.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 9379885 + ... + 9379955.

It is an arithmetic number, because the mean of its divisors is an integer number (5343408).

Almost surely, 2^665974320 is an apocalyptic number.

665974320 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 665974320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1282417920).

665974320 is an abundant number, since it is smaller than the sum of its proper divisors (1898861520).

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

665974320 is a wasteful number, since it uses less digits than its factorization.

665974320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 128 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 42.

The square root of 665974320 is about 25806.4782564379. The cubic root of 665974320 is about 873.2779497281.

The spelling of 665974320 in words is "six hundred sixty-five million, nine hundred seventy-four thousand, three hundred twenty".