66379400164 has 135 divisors (see below), whose sum is σ = 149582057891. Its totient is φ = 25753894320.

The previous prime is 66379400137. The next prime is 66379400167. The reversal of 66379400164 is 46100497366.

It is a happy number.

The square root of 66379400164 is 257642.

It is a perfect power (a square), and thus also a powerful number.

66379400164 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×66379400164² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66379400167) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 277737957 + ... + 277738195.

Almost surely, 2^66379400164 is an apocalyptic number.

66379400164 is the 257642-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66379400164

66379400164 is an abundant number, since it is smaller than the sum of its proper divisors (83202657727).

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

66379400164 is an equidigital number, since it uses as much as digits as its factorization.

66379400164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532 (or 259 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 46.

The spelling of 66379400164 in words is "sixty-six billion, three hundred seventy-nine million, four hundred thousand, one hundred sixty-four".