399097540 has 24 divisors (see below), whose sum is σ = 860757912. Its totient is φ = 155324160.

The previous prime is 399097483. The next prime is 399097547. The reversal of 399097540 is 45790993.

It can be written as a sum of positive squares in 4 ways, for example, as 88774084 + 310323456 = 9422^2 + 17616^2 .

It is not an unprimeable number, because it can be changed into a prime (399097547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 268921 + ... + 270400.

It is an arithmetic number, because the mean of its divisors is an integer number (35864913).

Almost surely, 2^399097540 is an apocalyptic number.

It is an amenable number.

399097540 is an abundant number, since it is smaller than the sum of its proper divisors (461660372).

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

399097540 is a wasteful number, since it uses less digits than its factorization.

399097540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539367 (or 539365 counting only the distinct ones).

The product of its (nonzero) digits is 306180, while the sum is 46.

The square root of 399097540 is about 19977.4257600923. The cubic root of 399097540 is about 736.2517673049.

The spelling of 399097540 in words is "three hundred ninety-nine million, ninety-seven thousand, five hundred forty".