66221867800 has 48 divisors (see below), whose sum is σ = 167962743000. Its totient is φ = 24080678400.

The previous prime is 66221867783. The next prime is 66221867809. The reversal of 66221867800 is 876812266.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66221867809) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15048225 + ... + 15052624.

Almost surely, 2^66221867800 is an apocalyptic number.

It is an amenable number.

66221867800 is an abundant number, since it is smaller than the sum of its proper divisors (101740875200).

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

66221867800 is a wasteful number, since it uses less digits than its factorization.

66221867800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30100876 (or 30100867 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 46.

The spelling of 66221867800 in words is "sixty-six billion, two hundred twenty-one million, eight hundred sixty-seven thousand, eight hundred".