399939425 has 12 divisors (see below), whose sum is σ = 498500460. Its totient is φ = 318289920.

The previous prime is 399939409. The next prime is 399939457. The reversal of 399939425 is 524939993.

It can be written as a sum of positive squares in 6 ways, for example, as 5678689 + 394260736 = 2383^2 + 19856^2 .

It is not a de Polignac number, because 399939425 - 2⁴ = 399939409 is a prime.

It is a hoax number, since the sum of its digits (53) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 36620 + ... + 46269.

It is an arithmetic number, because the mean of its divisors is an integer number (41541705).

Almost surely, 2^399939425 is an apocalyptic number.

It is an amenable number.

399939425 is a deficient number, since it is larger than the sum of its proper divisors (98561035).

399939425 is a wasteful number, since it uses less digits than its factorization.

399939425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83092 (or 83087 counting only the distinct ones).

The product of its digits is 2361960, while the sum is 53.

The square root of 399939425 is about 19998.4855676624. The cubic root of 399939425 is about 736.7691044824.

The spelling of 399939425 in words is "three hundred ninety-nine million, nine hundred thirty-nine thousand, four hundred twenty-five".