664019520 has 56 divisors (see below), whose sum is σ = 2108265024. Its totient is φ = 177071616.

The previous prime is 664019519. The next prime is 664019533. The reversal of 664019520 is 25910466.

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, 344884 + ... + 346803.

Almost surely, 2^664019520 is an apocalyptic number.

664019520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

664019520 is an abundant number, since it is smaller than the sum of its proper divisors (1444245504).

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

664019520 is a wasteful number, since it uses less digits than its factorization.

664019520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 691707 (or 691697 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 664019520 is about 25768.5762121232. The cubic root of 664019520 is about 872.4226831650.

Adding to 664019520 its reverse (25910466), we get a palindrome (689929986).

The spelling of 664019520 in words is "six hundred sixty-four million, nineteen thousand, five hundred twenty".