66642647880 has 64 divisors (see below), whose sum is σ = 199951905600. Its totient is φ = 17769242880.

The previous prime is 66642647873. The next prime is 66642647899. The reversal of 66642647880 is 8874624666.

It is a self number, because there is not a number n which added to its sum of digits gives 66642647880.

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, 1145331 + ... + 1202109.

It is an arithmetic number, because the mean of its divisors is an integer number (3124248525).

Almost surely, 2^66642647880 is an apocalyptic number.

66642647880 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66642647880 is an abundant number, since it is smaller than the sum of its proper divisors (133309257720).

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

66642647880 is a wasteful number, since it uses less digits than its factorization.

66642647880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66574 (or 66570 counting only the distinct ones).

The product of its (nonzero) digits is 18579456, while the sum is 57.

The spelling of 66642647880 in words is "sixty-six billion, six hundred forty-two million, six hundred forty-seven thousand, eight hundred eighty".