666655164 has 96 divisors (see below), whose sum is σ = 1984012800. Its totient is φ = 189630720.

The previous prime is 666655163. The next prime is 666655169. The reversal of 666655164 is 461556666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666655163) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 180367 + ... + 184025.

It is an arithmetic number, because the mean of its divisors is an integer number (20666800).

Almost surely, 2^666655164 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666655164, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (992006400).

666655164 is an abundant number, since it is smaller than the sum of its proper divisors (1317357636).

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

666655164 is a wasteful number, since it uses less digits than its factorization.

666655164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3920 (or 3912 counting only the distinct ones).

The product of its digits is 777600, while the sum is 45.

The square root of 666655164 is about 25819.6662255731. Note that the first 3 decimals coincide. The cubic root of 666655164 is about 873.5754404550.

The spelling of 666655164 in words is "six hundred sixty-six million, six hundred fifty-five thousand, one hundred sixty-four".