399073891 has 6 divisors (see below), whose sum is σ = 420169460. Its totient is φ = 377987508.

The previous prime is 399073849. The next prime is 399073903. The reversal of 399073891 is 198370993.

It is not a de Polignac number, because 399073891 - 2¹¹ = 399071843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399073091) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 84786 + ... + 89368.

Almost surely, 2^399073891 is an apocalyptic number.

399073891 is a deficient number, since it is larger than the sum of its proper divisors (21095569).

399073891 is an frugal number, since it uses more digits than its factorization.

399073891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9185 (or 4602 counting only the distinct ones).

The product of its (nonzero) digits is 367416, while the sum is 49.

The square root of 399073891 is about 19976.8338582469. The cubic root of 399073891 is about 736.2372245259.

The spelling of 399073891 in words is "three hundred ninety-nine million, seventy-three thousand, eight hundred ninety-one".