393534921 has 24 divisors (see below), whose sum is σ = 601616160. Its totient is φ = 227924736.

The previous prime is 393534907. The next prime is 393534931. The reversal of 393534921 is 129435393.

It is not a de Polignac number, because 393534921 - 2⁶ = 393534857 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 393534921.

It is not an unprimeable number, because it can be changed into a prime (393534931) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14211 + ... + 31448.

It is an arithmetic number, because the mean of its divisors is an integer number (25067340).

Almost surely, 2^393534921 is an apocalyptic number.

It is an amenable number.

393534921 is a deficient number, since it is larger than the sum of its proper divisors (208081239).

393534921 is a wasteful number, since it uses less digits than its factorization.

393534921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45705 (or 45692 counting only the distinct ones).

The product of its digits is 87480, while the sum is 39.

The square root of 393534921 is about 19837.7146113155. The cubic root of 393534921 is about 732.8151267124.

The spelling of 393534921 in words is "three hundred ninety-three million, five hundred thirty-four thousand, nine hundred twenty-one".