66221920089416 has 64 divisors (see below), whose sum is σ = 152820930192000. Its totient is φ = 26197491598848.

The previous prime is 66221920089401. The next prime is 66221920089419. The reversal of 66221920089416 is 61498002912266.

It is a Harshad number since it is a multiple of its sum of digits (56).

It is not an unprimeable number, because it can be changed into a prime (66221920089419) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 140708060 + ... + 141177908.

It is an arithmetic number, because the mean of its divisors is an integer number (2387827034250).

Almost surely, 2^{66221920089416} is an apocalyptic number.

It is an amenable number.

66221920089416 is an abundant number, since it is smaller than the sum of its proper divisors (86599010102584).

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

66221920089416 is a wasteful number, since it uses less digits than its factorization.

66221920089416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 663478 (or 663474 counting only the distinct ones).

The product of its (nonzero) digits is 4478976, while the sum is 56.

The spelling of 66221920089416 in words is "sixty-six trillion, two hundred twenty-one billion, nine hundred twenty million, eighty-nine thousand, four hundred sixteen".