399187040 has 96 divisors (see below), whose sum is σ = 1088204544. Its totient is φ = 135544320.

The previous prime is 399187037. The next prime is 399187051. The reversal of 399187040 is 40781993.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118175 + ... + 121505.

It is an arithmetic number, because the mean of its divisors is an integer number (11335464).

Almost surely, 2^399187040 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399187040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (544102272).

399187040 is an abundant number, since it is smaller than the sum of its proper divisors (689017504).

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

399187040 is a wasteful number, since it uses less digits than its factorization.

399187040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3460 (or 3452 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 399187040 is about 19979.6656628683. The cubic root of 399187040 is about 736.3067994725.

The spelling of 399187040 in words is "three hundred ninety-nine million, one hundred eighty-seven thousand, forty".