66906497774718 has 96 divisors (see below), whose sum is σ = 175992811737600. Its totient is φ = 17943882343488.

The previous prime is 66906497774687. The next prime is 66906497774719. The reversal of 66906497774718 is 81747779460966.

It is a happy number.

66906497774718 is a `hidden beast` number, since 6 + 6 + 9 + 0 + 6 + 497 + 77 + 47 + 18 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66906497774719) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 127938946 + ... + 128460837.

It is an arithmetic number, because the mean of its divisors is an integer number (1833258455600).

Almost surely, 2^{66906497774718} is an apocalyptic number.

66906497774718 is an abundant number, since it is smaller than the sum of its proper divisors (109086313962882).

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

66906497774718 is a wasteful number, since it uses less digits than its factorization.

66906497774718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256399926 (or 256399923 counting only the distinct ones).

The product of its (nonzero) digits is 5377010688, while the sum is 81.

The spelling of 66906497774718 in words is "sixty-six trillion, nine hundred six billion, four hundred ninety-seven million, seven hundred seventy-four thousand, seven hundred eighteen".