399391516800 has 384 divisors, whose sum is σ = 1464107184000. Its totient is φ = 106326282240.

The previous prime is 399391516763. The next prime is 399391516813. The reversal of 399391516800 is 8615193993.

399391516800 is a `hidden beast` number, since 3 + 99 + 39 + 1 + 516 + 8 + 0 + 0 = 666.

399391516800 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 56415661 + ... + 56422739.

It is an arithmetic number, because the mean of its divisors is an integer number (3812779125).

Almost surely, 2^399391516800 is an apocalyptic number.

399391516800 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399391516800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (732053592000).

399391516800 is an abundant number, since it is smaller than the sum of its proper divisors (1064715667200).

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

399391516800 is a wasteful number, since it uses less digits than its factorization.

399391516800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7765 (or 7742 counting only the distinct ones).

The product of its (nonzero) digits is 1574640, while the sum is 54.

The spelling of 399391516800 in words is "three hundred ninety-nine billion, three hundred ninety-one million, five hundred sixteen thousand, eight hundred".