665959320 has 320 divisors, whose sum is σ = 2450337120. Its totient is φ = 161243136.

The previous prime is 665959247. The next prime is 665959409. The reversal of 665959320 is 23959566.

665959320 is a `hidden beast` number, since 6 + 6 + 59 + 593 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 4085559 + ... + 4085721.

Almost surely, 2^665959320 is an apocalyptic number.

665959320 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 665959320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1225168560).

665959320 is an abundant number, since it is smaller than the sum of its proper divisors (1784377800).

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

665959320 is a wasteful number, since it uses less digits than its factorization.

665959320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296 (or 283 counting only the distinct ones).

The product of its (nonzero) digits is 437400, while the sum is 45.

The square root of 665959320 is about 25806.1876301014. The cubic root of 665959320 is about 873.2713932853.

The spelling of 665959320 in words is "six hundred sixty-five million, nine hundred fifty-nine thousand, three hundred twenty".