66808501810972 has 24 divisors (see below), whose sum is σ = 118151574850400. Its totient is φ = 33052763810880.

The previous prime is 66808501810877. The next prime is 66808501810979. The reversal of 66808501810972 is 27901810580866.

It is a self number, because there is not a number n which added to its sum of digits gives 66808501810972.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66808501810979) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 231707523 + ... + 231995674.

Almost surely, 2^{66808501810972} is an apocalyptic number.

It is an amenable number.

66808501810972 is a deficient number, since it is larger than the sum of its proper divisors (51343073039428).

66808501810972 is a wasteful number, since it uses less digits than its factorization.

66808501810972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463703581 (or 463703579 counting only the distinct ones).

The product of its (nonzero) digits is 11612160, while the sum is 61.

The spelling of 66808501810972 in words is "sixty-six trillion, eight hundred eight billion, five hundred one million, eight hundred ten thousand, nine hundred seventy-two".