399401440 has 48 divisors (see below), whose sum is σ = 984620448. Its totient is φ = 152813056.

The previous prime is 399401399. The next prime is 399401521. The reversal of 399401440 is 44104993.

It is a junction number, because it is equal to n+sod(n) for n = 399401396 and 399401405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50587 + ... + 57946.

It is an arithmetic number, because the mean of its divisors is an integer number (20512926).

Almost surely, 2^399401440 is an apocalyptic number.

It is an amenable number.

399401440 is an abundant number, since it is smaller than the sum of its proper divisors (585219008).

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

399401440 is a wasteful number, since it uses less digits than its factorization.

399401440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108571 (or 108563 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 399401440 is about 19985.0303977752. The cubic root of 399401440 is about 736.4385972748.

The spelling of 399401440 in words is "three hundred ninety-nine million, four hundred one thousand, four hundred forty".