399513840 has 160 divisors (see below), whose sum is σ = 1384411392. Its totient is φ = 94464000.

The previous prime is 399513797. The next prime is 399513853. The reversal of 399513840 is 48315993.

It is a super-2 number, since 2×399513840² = 319222616703091200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 399513792 and 399513801.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 106395 + ... + 110085.

Almost surely, 2^399513840 is an apocalyptic number.

399513840 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 399513840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (692205696).

399513840 is an abundant number, since it is smaller than the sum of its proper divisors (984897552).

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

399513840 is a wasteful number, since it uses less digits than its factorization.

399513840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3759 (or 3753 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 42.

The square root of 399513840 is about 19987.8423047612. The cubic root of 399513840 is about 736.5076739199.

The spelling of 399513840 in words is "three hundred ninety-nine million, five hundred thirteen thousand, eight hundred forty".