399637616 has 120 divisors (see below), whose sum is σ = 945653760. Its totient is φ = 160168320.

The previous prime is 399637607. The next prime is 399637633. The reversal of 399637616 is 616736993.

It is a happy number.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5058665 + ... + 5058743.

It is an arithmetic number, because the mean of its divisors is an integer number (7880448).

Almost surely, 2^399637616 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399637616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (472826880).

399637616 is an abundant number, since it is smaller than the sum of its proper divisors (546016144).

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

399637616 is a wasteful number, since it uses less digits than its factorization.

399637616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203 (or 166 counting only the distinct ones).

The product of its digits is 1102248, while the sum is 50.

The square root of 399637616 is about 19990.9383471612. The cubic root of 399637616 is about 736.5837268221.

The spelling of 399637616 in words is "three hundred ninety-nine million, six hundred thirty-seven thousand, six hundred sixteen".