399926865 has 32 divisors (see below), whose sum is σ = 690673536. Its totient is φ = 196439040.

The previous prime is 399926861. The next prime is 399926867. The reversal of 399926865 is 568629993.

It is not a de Polignac number, because 399926865 - 2² = 399926861 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (399926861) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 93657 + ... + 97833.

It is an arithmetic number, because the mean of its divisors is an integer number (21583548).

Almost surely, 2^399926865 is an apocalyptic number.

It is an amenable number.

399926865 is a deficient number, since it is larger than the sum of its proper divisors (290746671).

399926865 is a wasteful number, since it uses less digits than its factorization.

399926865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4689.

The product of its digits is 6298560, while the sum is 57.

The square root of 399926865 is about 19998.1715414185. The cubic root of 399926865 is about 736.7613917171.

The spelling of 399926865 in words is "three hundred ninety-nine million, nine hundred twenty-six thousand, eight hundred sixty-five".