666156204 has 48 divisors (see below), whose sum is σ = 1973798400. Its totient is φ = 190330128.

The previous prime is 666156157. The next prime is 666156217. The reversal of 666156204 is 402651666.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 439824 + ... + 441335.

It is an arithmetic number, because the mean of its divisors is an integer number (41120800).

Almost surely, 2^666156204 is an apocalyptic number.

It is an amenable number.

666156204 is an abundant number, since it is smaller than the sum of its proper divisors (1307642196).

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

666156204 is a wasteful number, since it uses less digits than its factorization.

666156204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 881179 (or 881171 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 666156204 is about 25810.0020147229. The cubic root of 666156204 is about 873.3574426976.

The spelling of 666156204 in words is "six hundred sixty-six million, one hundred fifty-six thousand, two hundred four".