664033640 has 32 divisors (see below), whose sum is σ = 1542274560. Its totient is φ = 257044800.

The previous prime is 664033639. The next prime is 664033673. The reversal of 664033640 is 46330466.

It is a junction number, because it is equal to n+sod(n) for n = 664033597 and 664033606.

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, 266516 + ... + 268995.

It is an arithmetic number, because the mean of its divisors is an integer number (48196080).

Almost surely, 2^664033640 is an apocalyptic number.

It is an amenable number.

664033640 is an abundant number, since it is smaller than the sum of its proper divisors (878240920).

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

664033640 is a wasteful number, since it uses less digits than its factorization.

664033640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 535553 (or 535549 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 32.

The square root of 664033640 is about 25768.8501877752. The cubic root of 664033640 is about 872.4288669797.

The spelling of 664033640 in words is "six hundred sixty-four million, thirty-three thousand, six hundred forty".