393868393 has 8 divisors (see below), whose sum is σ = 420729768. Its totient is φ = 367417344.

The previous prime is 393868357. The next prime is 393868421.

It is a happy number.

393868393 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 106667584 + 287200809 = 10328^2 + 16947^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-393868393 is a prime.

It is a super-2 number, since 2×393868393² = 310264622008804898, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 393868393.

It is not an unprimeable number, because it can be changed into a prime (393868303) 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, 100596 + ... + 104437.

It is an arithmetic number, because the mean of its divisors is an integer number (52591221).

Almost surely, 2^393868393 is an apocalyptic number.

It is an amenable number.

393868393 is a deficient number, since it is larger than the sum of its proper divisors (26861375).

393868393 is a wasteful number, since it uses less digits than its factorization.

393868393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205163.

The product of its digits is 2519424, while the sum is 52.

The square root of 393868393 is about 19846.1178319590. The cubic root of 393868393 is about 733.0220582281.

The spelling of 393868393 in words is "three hundred ninety-three million, eight hundred sixty-eight thousand, three hundred ninety-three".