399831120 has 320 divisors, whose sum is σ = 1537401600. Its totient is φ = 94832640.

The previous prime is 399831101. The next prime is 399831163. The reversal of 399831120 is 21138993.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 814075 + ... + 814565.

It is an arithmetic number, because the mean of its divisors is an integer number (4804380).

Almost surely, 2^399831120 is an apocalyptic number.

399831120 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 399831120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (768700800).

399831120 is an abundant number, since it is smaller than the sum of its proper divisors (1137570480).

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

399831120 is a wasteful number, since it uses less digits than its factorization.

399831120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 555 (or 543 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 399831120 is about 19995.7775542738. Note that the first 3 decimals coincide. The cubic root of 399831120 is about 736.7025919250.

The spelling of 399831120 in words is "three hundred ninety-nine million, eight hundred thirty-one thousand, one hundred twenty".