66617515584 has 70 divisors (see below), whose sum is σ = 197475200934. Its totient is φ = 22205836800.

The previous prime is 66617515571. The next prime is 66617515631. The reversal of 66617515584 is 48551571666.

It can be written as a sum of positive squares in only one way, i.e., 65884622400 + 732893184 = 256680^2 + 27072^2 .

It is a super-2 number, since 2×66617515584² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 66617515584.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 6420117 + ... + 6430484.

Almost surely, 2^66617515584 is an apocalyptic number.

66617515584 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

66617515584 is an abundant number, since it is smaller than the sum of its proper divisors (130857685350).

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

66617515584 is a wasteful number, since it uses less digits than its factorization.

66617515584 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12850625 (or 12850606 counting only the distinct ones).

The product of its digits is 6048000, while the sum is 54.

The spelling of 66617515584 in words is "sixty-six billion, six hundred seventeen million, five hundred fifteen thousand, five hundred eighty-four".