399215220 has 24 divisors (see below), whose sum is σ = 1117802784. Its totient is φ = 106457376.

The previous prime is 399215183. The next prime is 399215281. The reversal of 399215220 is 22512993.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3326734 + ... + 3326853.

It is an arithmetic number, because the mean of its divisors is an integer number (46575116).

Almost surely, 2^399215220 is an apocalyptic number.

399215220 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

399215220 is an abundant number, since it is smaller than the sum of its proper divisors (718587564).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

399215220 is a wasteful number, since it uses less digits than its factorization.

399215220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6653599 (or 6653597 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 399215220 is about 19980.3708674289. The cubic root of 399215220 is about 736.3241252164.

The spelling of 399215220 in words is "three hundred ninety-nine million, two hundred fifteen thousand, two hundred twenty".