665040960 has 252 divisors, whose sum is σ = 2379401388. Its totient is φ = 170366976.

The previous prime is 665040919. The next prime is 665041001. The reversal of 665040960 is 69040566.

It is a happy number.

665040960 is a `hidden beast` number, since 66 + 504 + 0 + 96 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (665040919) and next prime (665041001).

It can be written as a sum of positive squares in 2 ways, for example, as 434972736 + 230068224 = 20856^2 + 15168^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 8418201 + ... + 8418279.

It is an arithmetic number, because the mean of its divisors is an integer number (9442069).

Almost surely, 2^665040960 is an apocalyptic number.

665040960 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 665040960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1189700694).

665040960 is an abundant number, since it is smaller than the sum of its proper divisors (1714360428).

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

665040960 is a wasteful number, since it uses less digits than its factorization.

665040960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218 (or 126 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 665040960 is about 25788.3880845624. The cubic root of 665040960 is about 872.8697939591.

The spelling of 665040960 in words is "six hundred sixty-five million, forty thousand, nine hundred sixty".