399155131 has 12 divisors (see below), whose sum is σ = 413354592. Its totient is φ = 385400000.

The previous prime is 399155129. The next prime is 399155191. The reversal of 399155131 is 131551993.

It is not a de Polignac number, because 399155131 - 2¹ = 399155129 is a prime.

It is a super-2 number, since 2×399155131² = 318649637207254322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399155191) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 168606 + ... + 170956.

It is an arithmetic number, because the mean of its divisors is an integer number (34446216).

Almost surely, 2^399155131 is an apocalyptic number.

399155131 is a deficient number, since it is larger than the sum of its proper divisors (14199461).

399155131 is a wasteful number, since it uses less digits than its factorization.

399155131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2534 (or 2493 counting only the distinct ones).

The product of its digits is 18225, while the sum is 37.

The square root of 399155131 is about 19978.8671100240. The cubic root of 399155131 is about 736.2871800649.

The spelling of 399155131 in words is "three hundred ninety-nine million, one hundred fifty-five thousand, one hundred thirty-one".