399960000 has 420 divisors, whose sum is σ = 1578263544. Its totient is φ = 96000000.

The previous prime is 399959983. The next prime is 399960007. The reversal of 399960000 is 69993.

It is a Cunningham number, because it is equal to 19999²-1.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399960007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 3959950 + ... + 3960050.

Almost surely, 2^399960000 is an apocalyptic number.

399960000 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 399960000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (789131772).

399960000 is an abundant number, since it is smaller than the sum of its proper divisors (1178303544).

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

399960000 is a wasteful number, since it uses less digits than its factorization.

399960000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 36.

The square root of 399960000 is about 19998.9999749987. Note that the first 4 decimals coincide. The cubic root of 399960000 is about 736.7817386994.

The spelling of 399960000 in words is "three hundred ninety-nine million, nine hundred sixty thousand".