664861166 has 16 divisors (see below), whose sum is σ = 1023775200. Its totient is φ = 323637120.

The previous prime is 664861159. The next prime is 664861187. The reversal of 664861166 is 661168466.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31610 + ... + 48258.

It is an arithmetic number, because the mean of its divisors is an integer number (63985950).

Almost surely, 2^664861166 is an apocalyptic number.

664861166 is a deficient number, since it is larger than the sum of its proper divisors (358914034).

664861166 is a wasteful number, since it uses less digits than its factorization.

664861166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17179.

The product of its digits is 248832, while the sum is 44.

The square root of 664861166 is about 25784.9019001430. The cubic root of 664861166 is about 872.7911266759.

The spelling of 664861166 in words is "six hundred sixty-four million, eight hundred sixty-one thousand, one hundred sixty-six".