399618019836 has 72 divisors (see below), whose sum is σ = 1159282575360. Its totient is φ = 113698833696.

The previous prime is 399618019751. The next prime is 399618019841. The reversal of 399618019836 is 638910816993.

399618019836 is a `hidden beast` number, since 3 + 9 + 9 + 618 + 0 + 1 + 9 + 8 + 3 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3257316 + ... + 3377771.

It is an arithmetic number, because the mean of its divisors is an integer number (16101146880).

Almost surely, 2^399618019836 is an apocalyptic number.

399618019836 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

399618019836 is an abundant number, since it is smaller than the sum of its proper divisors (759664555524).

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

399618019836 is a wasteful number, since it uses less digits than its factorization.

399618019836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6635343 (or 6635338 counting only the distinct ones).

The product of its (nonzero) digits is 15116544, while the sum is 63.

It can be divided in two parts, 3996180 and 19836, that added together give a square (4016016 = 2004²).

The spelling of 399618019836 in words is "three hundred ninety-nine billion, six hundred eighteen million, nineteen thousand, eight hundred thirty-six".