399160442 has 12 divisors (see below), whose sum is σ = 636033390. Its totient is φ = 187839936.

The previous prime is 399160427. The next prime is 399160451. The reversal of 399160442 is 244061993.

It is a Cunningham number, because it is equal to 19979²+1.

It can be written as a sum of positive squares in 3 ways, for example, as 399160441 + 1 = 19979^2 + 1^2 .

It is a junction number, because it is equal to n+sod(n) for n = 399160396 and 399160405.

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 5 ways as a sum of consecutive naturals, for example, 344717 + ... + 345872.

Almost surely, 2^399160442 is an apocalyptic number.

399160442 is a deficient number, since it is larger than the sum of its proper divisors (236872948).

399160442 is a wasteful number, since it uses less digits than its factorization.

399160442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 690625 (or 690608 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 399160442 is about 19979.0000250263. Note that the first 4 decimals coincide. The cubic root of 399160442 is about 736.2904456322.

It can be divided in two parts, 399160 and 442, that multiplied together give a triangular number (176428720 = T₁₈₇₈₄).

The spelling of 399160442 in words is "three hundred ninety-nine million, one hundred sixty thousand, four hundred forty-two".