393939644 has 24 divisors (see below), whose sum is σ = 807098208. Its totient is φ = 164712960.

The previous prime is 393939587. The next prime is 393939677. The reversal of 393939644 is 446939393.

It is a happy number.

It is a super-2 number, since 2×393939644² = 310376886229693472, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 393939592 and 393939601.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 170429 + ... + 172724.

It is an arithmetic number, because the mean of its divisors is an integer number (33629092).

Almost surely, 2^393939644 is an apocalyptic number.

It is an amenable number.

393939644 is an abundant number, since it is smaller than the sum of its proper divisors (413158564).

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

393939644 is a wasteful number, since it uses less digits than its factorization.

393939644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343205 (or 343203 counting only the distinct ones).

The product of its digits is 1889568, while the sum is 50.

The square root of 393939644 is about 19847.9128373741. The cubic root of 393939644 is about 733.0662569220.

The spelling of 393939644 in words is "three hundred ninety-three million, nine hundred thirty-nine thousand, six hundred forty-four".