399507323904 has 880 divisors, whose sum is σ = 1363189988160. Its totient is φ = 115617300480.

The previous prime is 399507323903. The next prime is 399507323981. The reversal of 399507323904 is 409323705993.

It is a super-2 number, since 2×399507323904² (a number of 24 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399507323903) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2207222694 + ... + 2207222874.

It is an arithmetic number, because the mean of its divisors is an integer number (1549079532).

Almost surely, 2^399507323904 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 399507323904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (681594994080).

399507323904 is an abundant number, since it is smaller than the sum of its proper divisors (963682664256).

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

399507323904 is a wasteful number, since it uses less digits than its factorization.

399507323904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338 (or 311 counting only the distinct ones).

The product of its (nonzero) digits is 5511240, while the sum is 54.

The spelling of 399507323904 in words is "three hundred ninety-nine billion, five hundred seven million, three hundred twenty-three thousand, nine hundred four".