399878811 has 24 divisors (see below), whose sum is σ = 618967440. Its totient is φ = 247873536.

The previous prime is 399878797. The next prime is 399878819. The reversal of 399878811 is 118878993.

It is not a de Polignac number, because 399878811 - 2⁵ = 399878779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (399878819) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3046 + ... + 28443.

It is an arithmetic number, because the mean of its divisors is an integer number (25790310).

Almost surely, 2^399878811 is an apocalyptic number.

399878811 is a deficient number, since it is larger than the sum of its proper divisors (219088629).

399878811 is a wasteful number, since it uses less digits than its factorization.

399878811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31595 (or 31592 counting only the distinct ones).

The product of its digits is 870912, while the sum is 54.

The square root of 399878811 is about 19996.9700454844. The cubic root of 399878811 is about 736.7318815298.

It can be divided in two parts, 399878 and 811, that added together give a square (400689 = 633²).

The spelling of 399878811 in words is "three hundred ninety-nine million, eight hundred seventy-eight thousand, eight hundred eleven".