664764 has 24 divisors (see below), whose sum is σ = 1602048. Its totient is φ = 214320.

The previous prime is 664757. The next prime is 664771. The reversal of 664764 is 467466.

It is an interprime number because it is at equal distance from previous prime (664757) and next prime (664771).

It is a super-2 number, since 2×664764² = 883822351392, which contains 22 as substring.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 664764.

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, 522 + ... + 1265.

It is an arithmetic number, because the mean of its divisors is an integer number (66752).

2⁶⁶⁴⁷⁶⁴ is an apocalyptic number.

It is an amenable number.

664764 is an abundant number, since it is smaller than the sum of its proper divisors (937284).

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

664764 is a wasteful number, since it uses less digits than its factorization.

664764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1825 (or 1823 counting only the distinct ones).

The product of its digits is 24192, while the sum is 33.

The square root of 664764 is about 815.3306077905. The cubic root of 664764 is about 87.2748606644.

The spelling of 664764 in words is "six hundred sixty-four thousand, seven hundred sixty-four".