66989716464 has 80 divisors (see below), whose sum is σ = 196997462784. Its totient is φ = 19417305600.

The previous prime is 66989716447. The next prime is 66989716471. The reversal of 66989716464 is 46461798966.

It is a super-2 number, since 2×66989716464² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a junction number, because it is equal to n+sod(n) for n = 66989716395 and 66989716404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2745997 + ... + 2770284.

Almost surely, 2^66989716464 is an apocalyptic number.

It is an amenable number.

66989716464 is an abundant number, since it is smaller than the sum of its proper divisors (130007746320).

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

66989716464 is a wasteful number, since it uses less digits than its factorization.

66989716464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5516326 (or 5516320 counting only the distinct ones).

The product of its digits is 94058496, while the sum is 66.

The spelling of 66989716464 in words is "sixty-six billion, nine hundred eighty-nine million, seven hundred sixteen thousand, four hundred sixty-four".