399418131 has 16 divisors (see below), whose sum is σ = 629625600. Its totient is φ = 220368288.

The previous prime is 399418109. The next prime is 399418139. The reversal of 399418131 is 131814993.

It is a happy number.

It is not a de Polignac number, because 399418131 - 2²⁵ = 365863699 is a prime.

It is a super-2 number, since 2×399418131² = 319069686743066322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 399418131.

It is not an unprimeable number, because it can be changed into a prime (399418139) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 327321 + ... + 328538.

It is an arithmetic number, because the mean of its divisors is an integer number (39351600).

Almost surely, 2^399418131 is an apocalyptic number.

399418131 is a deficient number, since it is larger than the sum of its proper divisors (230207469).

399418131 is a wasteful number, since it uses less digits than its factorization.

399418131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 655898.

The product of its digits is 23328, while the sum is 39.

The square root of 399418131 is about 19985.4479809686. The cubic root of 399418131 is about 736.4488557300.

The spelling of 399418131 in words is "three hundred ninety-nine million, four hundred eighteen thousand, one hundred thirty-one".