66715655600 has 120 divisors (see below), whose sum is σ = 176491078848. Its totient is φ = 24033337600.

The previous prime is 66715655561. The next prime is 66715655731. The reversal of 66715655600 is 655651766.

It is a super-2 number, since 2×66715655600² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 399947 + ... + 541653.

Almost surely, 2^66715655600 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66715655600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88245539424).

66715655600 is an abundant number, since it is smaller than the sum of its proper divisors (109775423248).

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

66715655600 is a wasteful number, since it uses less digits than its factorization.

66715655600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141843 (or 141832 counting only the distinct ones).

The product of its (nonzero) digits is 1134000, while the sum is 47.

The spelling of 66715655600 in words is "sixty-six billion, seven hundred fifteen million, six hundred fifty-five thousand, six hundred".