399864685220 has 432 divisors, whose sum is σ = 1181093114880. Its totient is φ = 112577794560.

The previous prime is 399864685201. The next prime is 399864685223. The reversal of 399864685220 is 22586468993.

It is a Smith number, since the sum of its digits (62) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (399864685223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 72449621 + ... + 72455139.

It is an arithmetic number, because the mean of its divisors is an integer number (2734011840).

Almost surely, 2^399864685220 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 399864685220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (590546557440).

399864685220 is an abundant number, since it is smaller than the sum of its proper divisors (781228429660).

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

399864685220 is a wasteful number, since it uses less digits than its factorization.

399864685220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5624 (or 5604 counting only the distinct ones).

The product of its (nonzero) digits is 44789760, while the sum is 62.

The spelling of 399864685220 in words is "three hundred ninety-nine billion, eight hundred sixty-four million, six hundred eighty-five thousand, two hundred twenty".