66757864 has 8 divisors (see below), whose sum is σ = 125171010. Its totient is φ = 33378928.

The previous prime is 66757853. The next prime is 66757877. The reversal of 66757864 is 46875766.

It can be written as a sum of positive squares in only one way, i.e., 37920964 + 28836900 = 6158^2 + 5370^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×66757864² = 8913224811684992, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4172359 + ... + 4172374.

Almost surely, 2^66757864 is an apocalyptic number.

It is an amenable number.

66757864 is a deficient number, since it is larger than the sum of its proper divisors (58413146).

66757864 is a wasteful number, since it uses less digits than its factorization.

66757864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8344739 (or 8344735 counting only the distinct ones).

The product of its digits is 1693440, while the sum is 49.

The square root of 66757864 is about 8170.5485739943. The cubic root of 66757864 is about 405.6649423275.

The spelling of 66757864 in words is "sixty-six million, seven hundred fifty-seven thousand, eight hundred sixty-four".