399960000000 has 960 divisors, whose sum is σ = 1589642024256. Its totient is φ = 96000000000.

The previous prime is 399959999987. The next prime is 399960000019. The reversal of 399960000000 is 69993.

It is a tau number, because it is divible by the number of its divisors (960).

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

It is a self number, because there is not a number n which added to its sum of digits gives 399960000000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3959999950 + ... + 3960000050.

Almost surely, 2^399960000000 is an apocalyptic number.

399960000000 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 399960000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (794821012128).

399960000000 is an abundant number, since it is smaller than the sum of its proper divisors (1189682024256).

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

399960000000 is an frugal number, since it uses more digits than its factorization.

399960000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171 (or 122 counting only the distinct ones).

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

Adding to 399960000000 its reverse (69993), we get a palindrome (399960069993).

The spelling of 399960000000 in words is "three hundred ninety-nine billion, nine hundred sixty million", and thus it is an aban number.