664423120 has 40 divisors (see below), whose sum is σ = 1545856416. Its totient is φ = 265584768.

The previous prime is 664423117. The next prime is 664423129. The reversal of 664423120 is 21324466.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664423129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 222759 + ... + 225721.

Almost surely, 2^664423120 is an apocalyptic number.

It is an amenable number.

664423120 is an abundant number, since it is smaller than the sum of its proper divisors (881433296).

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

664423120 is a wasteful number, since it uses less digits than its factorization.

664423120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5779 (or 5773 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 664423120 is about 25776.4062661962. The cubic root of 664423120 is about 872.5994041144.

Adding to 664423120 its reverse (21324466), we get a palindrome (685747586).

The spelling of 664423120 in words is "six hundred sixty-four million, four hundred twenty-three thousand, one hundred twenty".