66757975794 has 64 divisors (see below), whose sum is σ = 149480208000. Its totient is φ = 22083558336.

The previous prime is 66757975789. The next prime is 66757975849. The reversal of 66757975794 is 49757975766.

It is a happy number.

It is a super-2 number, since 2×66757975794² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11044137 + ... + 11050179.

It is an arithmetic number, because the mean of its divisors is an integer number (2335628250).

Almost surely, 2^66757975794 is an apocalyptic number.

66757975794 is an abundant number, since it is smaller than the sum of its proper divisors (82722232206).

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

66757975794 is a wasteful number, since it uses less digits than its factorization.

66757975794 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7576 (or 7570 counting only the distinct ones).

The product of its digits is 700131600, while the sum is 72.

The spelling of 66757975794 in words is "sixty-six billion, seven hundred fifty-seven million, nine hundred seventy-five thousand, seven hundred ninety-four".