399139097 has 4 divisors (see below), whose sum is σ = 456158976. Its totient is φ = 342119220.

The previous prime is 399139063. The next prime is 399139127. The reversal of 399139097 is 790931993.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 399139097 - 2⁸ = 399138841 is a prime.

It is not an unprimeable number, because it can be changed into a prime (399139007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28509929 + ... + 28509942.

It is an arithmetic number, because the mean of its divisors is an integer number (114039744).

Almost surely, 2^399139097 is an apocalyptic number.

It is an amenable number.

399139097 is a deficient number, since it is larger than the sum of its proper divisors (57019879).

399139097 is an equidigital number, since it uses as much as digits as its factorization.

399139097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57019878.

The product of its (nonzero) digits is 413343, while the sum is 50.

The square root of 399139097 is about 19978.4658319902. The cubic root of 399139097 is about 736.2773210854.

The spelling of 399139097 in words is "three hundred ninety-nine million, one hundred thirty-nine thousand, ninety-seven".