399961584 has 160 divisors (see below), whose sum is σ = 1326343680. Its totient is φ = 114048000.

The previous prime is 399961561. The next prime is 399961589. The reversal of 399961584 is 485169993.

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

It is a self number, because there is not a number n which added to its sum of digits gives 399961584.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399961589) 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 31 ways as a sum of consecutive naturals, for example, 78309 + ... + 83259.

It is an arithmetic number, because the mean of its divisors is an integer number (8289648).

Almost surely, 2^399961584 is an apocalyptic number.

399961584 is a gapful number since it is divisible by the number (34) 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 399961584, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (663171840).

399961584 is an abundant number, since it is smaller than the sum of its proper divisors (926382096).

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

399961584 is a wasteful number, since it uses less digits than its factorization.

399961584 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4996 (or 4984 counting only the distinct ones).

The product of its digits is 2099520, while the sum is 54.

The square root of 399961584 is about 19999.0395769397. The cubic root of 399961584 is about 736.7827113472.

The spelling of 399961584 in words is "three hundred ninety-nine million, nine hundred sixty-one thousand, five hundred eighty-four".