66221952 has 64 divisors (see below), whose sum is σ = 181608960. Its totient is φ = 21358080.

The previous prime is 66221951. The next prime is 66221959. The reversal of 66221952 is 25912266.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66221951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9123 + ... + 14685.

It is an arithmetic number, because the mean of its divisors is an integer number (2837640).

Almost surely, 2^66221952 is an apocalyptic number.

66221952 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66221952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90804480).

66221952 is an abundant number, since it is smaller than the sum of its proper divisors (115387008).

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

66221952 is a wasteful number, since it uses less digits than its factorization.

66221952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5611 (or 5599 counting only the distinct ones).

The product of its digits is 12960, while the sum is 33.

The square root of 66221952 is about 8137.6871407053. The cubic root of 66221952 is about 404.5765059576.

The spelling of 66221952 in words is "sixty-six million, two hundred twenty-one thousand, nine hundred fifty-two".