399259980 has 144 divisors (see below), whose sum is σ = 1403910144. Its totient is φ = 89953920.

The previous prime is 399259979. The next prime is 399259997. The reversal of 399259980 is 89952993.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 87229 + ... + 91691.

It is an arithmetic number, because the mean of its divisors is an integer number (9749376).

Almost surely, 2^399259980 is an apocalyptic number.

399259980 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 399259980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (701955072).

399259980 is an abundant number, since it is smaller than the sum of its proper divisors (1004650164).

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

399259980 is a wasteful number, since it uses less digits than its factorization.

399259980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4556 (or 4551 counting only the distinct ones).

The product of its (nonzero) digits is 1574640, while the sum is 54.

The square root of 399259980 is about 19981.4909353632. The cubic root of 399259980 is about 736.3516430686.

The spelling of 399259980 in words is "three hundred ninety-nine million, two hundred fifty-nine thousand, nine hundred eighty".