399641930 has 32 divisors (see below), whose sum is σ = 726824016. Its totient is φ = 158206464.

The previous prime is 399641917. The next prime is 399641941. The reversal of 399641930 is 39146993.

It can be written as a sum of positive squares in 8 ways, for example, as 116359369 + 283282561 = 10787^2 + 16831^2 .

It is a Curzon 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, 717212 + ... + 717768.

Almost surely, 2^399641930 is an apocalyptic number.

399641930 is a deficient number, since it is larger than the sum of its proper divisors (327182086).

399641930 is a wasteful number, since it uses less digits than its factorization.

399641930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178.

The product of its (nonzero) digits is 157464, while the sum is 44.

The square root of 399641930 is about 19991.0462457571. The cubic root of 399641930 is about 736.5863772322.

The spelling of 399641930 in words is "three hundred ninety-nine million, six hundred forty-one thousand, nine hundred thirty".