66975520 has 24 divisors (see below), whose sum is σ = 158230044. Its totient is φ = 26790144.

The previous prime is 66975497. The next prime is 66975521. The reversal of 66975520 is 2557966.

It can be written as a sum of positive squares in 2 ways, for example, as 65999376 + 976144 = 8124^2 + 988^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (66975521) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 209139 + ... + 209458.

Almost surely, 2^66975520 is an apocalyptic number.

It is an amenable number.

66975520 is an abundant number, since it is smaller than the sum of its proper divisors (91254524).

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

66975520 is a wasteful number, since it uses less digits than its factorization.

66975520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418612 (or 418604 counting only the distinct ones).

The product of its (nonzero) digits is 113400, while the sum is 40.

The square root of 66975520 is about 8183.8572812580. The cubic root of 66975520 is about 406.1053380002.

The spelling of 66975520 in words is "sixty-six million, nine hundred seventy-five thousand, five hundred twenty".