399639600 has 180 divisors, whose sum is σ = 1431997632. Its totient is φ = 103104000.

The previous prime is 399639599. The next prime is 399639601. The reversal of 399639600 is 6936993.

399639600 is a `hidden beast` number, since 3 + 9 + 9 + 6 + 39 + 600 = 666.

It is an interprime number because it is at equal distance from previous prime (399639599) and next prime (399639601).

It is a tau number, because it is divible by the number of its divisors (180).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (399639601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 109810 + ... + 113390.

Almost surely, 2^399639600 is an apocalyptic number.

399639600 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 399639600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (715998816).

399639600 is an abundant number, since it is smaller than the sum of its proper divisors (1032358032).

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

399639600 is a wasteful number, since it uses less digits than its factorization.

399639600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3636 (or 3622 counting only the distinct ones).

The product of its (nonzero) digits is 236196, while the sum is 45.

The square root of 399639600 is about 19990.9879695827. The cubic root of 399639600 is about 736.5849457428.

The spelling of 399639600 in words is "three hundred ninety-nine million, six hundred thirty-nine thousand, six hundred".