664270164 has 18 divisors (see below), whose sum is σ = 1679127450. Its totient is φ = 221423376.

The previous prime is 664270141. The next prime is 664270261. The reversal of 664270164 is 461072466.

664270164 is a `hidden beast` number, since 6 + 642 + 7 + 0 + 1 + 6 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 648109764 + 16160400 = 25458^2 + 4020^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 18451949 = 664270164 / (6 + 6 + 4 + 2 + 7 + 0 + 1 + 6 + 4).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9225939 + ... + 9226010.

Almost surely, 2^664270164 is an apocalyptic number.

It is an amenable number.

664270164 is an abundant number, since it is smaller than the sum of its proper divisors (1014857286).

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

664270164 is a wasteful number, since it uses less digits than its factorization.

664270164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18451959 (or 18451954 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 664270164 is about 25773.4391185965. The cubic root of 664270164 is about 872.5324389764.

The spelling of 664270164 in words is "six hundred sixty-four million, two hundred seventy thousand, one hundred sixty-four".