399670155 has 24 divisors (see below), whose sum is σ = 693452448. Its totient is φ = 212944896.

The previous prime is 399670151. The next prime is 399670163. The reversal of 399670155 is 551076993.

It is not a de Polignac number, because 399670155 - 2² = 399670151 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 399670155.

It is not an unprimeable number, because it can be changed into a prime (399670151) 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, 48034 + ... + 55736.

It is an arithmetic number, because the mean of its divisors is an integer number (28893852).

Almost surely, 2^399670155 is an apocalyptic number.

399670155 is a deficient number, since it is larger than the sum of its proper divisors (293782293).

399670155 is a wasteful number, since it uses less digits than its factorization.

399670155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8867 (or 8864 counting only the distinct ones).

The product of its (nonzero) digits is 255150, while the sum is 45.

The square root of 399670155 is about 19991.7521743343. The cubic root of 399670155 is about 736.6037174723.

The spelling of 399670155 in words is "three hundred ninety-nine million, six hundred seventy thousand, one hundred fifty-five".