393935664 has 40 divisors (see below), whose sum is σ = 1071231040. Its totient is φ = 124400448.

The previous prime is 393935639. The next prime is 393935669. The reversal of 393935664 is 466539393.

It is a happy number.

It is a super-2 number, since 2×393935664² = 310370614742241792, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (393935669) 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, 215062 + ... + 216885.

It is an arithmetic number, because the mean of its divisors is an integer number (26780776).

Almost surely, 2^393935664 is an apocalyptic number.

It is an amenable number.

393935664 is an abundant number, since it is smaller than the sum of its proper divisors (677295376).

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

393935664 is a wasteful number, since it uses less digits than its factorization.

393935664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 431977 (or 431971 counting only the distinct ones).

The product of its digits is 1574640, while the sum is 48.

The square root of 393935664 is about 19847.8125746894. The cubic root of 393935664 is about 733.0637881737.

The spelling of 393935664 in words is "three hundred ninety-three million, nine hundred thirty-five thousand, six hundred sixty-four".