399223618 has 16 divisors (see below), whose sum is σ = 614592000. Its totient is φ = 194422032.

The previous prime is 399223603. The next prime is 399223633. The reversal of 399223618 is 816322993.

It is an interprime number because it is at equal distance from previous prime (399223603) and next prime (399223633).

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, 2658 + ... + 28381.

It is an arithmetic number, because the mean of its divisors is an integer number (38412000).

Almost surely, 2^399223618 is an apocalyptic number.

399223618 is a deficient number, since it is larger than the sum of its proper divisors (215368382).

399223618 is a wasteful number, since it uses less digits than its factorization.

399223618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31209.

The product of its digits is 139968, while the sum is 43.

The square root of 399223618 is about 19980.5810225829. The cubic root of 399223618 is about 736.3292883518.

The spelling of 399223618 in words is "three hundred ninety-nine million, two hundred twenty-three thousand, six hundred eighteen".