399142431 has 16 divisors (see below), whose sum is σ = 592705120. Its totient is φ = 265472640.

The previous prime is 399142427. The next prime is 399142433. The reversal of 399142431 is 134241993.

It is not a de Polignac number, because 399142431 - 2² = 399142427 is a prime.

It is a super-2 number, since 2×399142431² = 318629360449179522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399142433) 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, 5380 + ... + 28761.

It is an arithmetic number, because the mean of its divisors is an integer number (37044070).

Almost surely, 2^399142431 is an apocalyptic number.

399142431 is a deficient number, since it is larger than the sum of its proper divisors (193562689).

399142431 is a wasteful number, since it uses less digits than its factorization.

399142431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34583 (or 34577 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 399142431 is about 19978.5492716563. The cubic root of 399142431 is about 736.2793711157.

The spelling of 399142431 in words is "three hundred ninety-nine million, one hundred forty-two thousand, four hundred thirty-one".