399446945 has 8 divisors (see below), whose sum is σ = 480850344. Its totient is φ = 318548224.

The previous prime is 399446917. The next prime is 399446951. The reversal of 399446945 is 549644993.

It can be written as a sum of positive squares in 4 ways, for example, as 9265936 + 390181009 = 3044^2 + 19753^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 399446945 - 2⁸ = 399446689 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124424 + ... + 127593.

It is an arithmetic number, because the mean of its divisors is an integer number (60106293).

Almost surely, 2^399446945 is an apocalyptic number.

It is an amenable number.

399446945 is a deficient number, since it is larger than the sum of its proper divisors (81403399).

399446945 is a wasteful number, since it uses less digits than its factorization.

399446945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252339.

The product of its digits is 4199040, while the sum is 53.

The square root of 399446945 is about 19986.1688424770. The cubic root of 399446945 is about 736.4665644296.

It can be divided in two parts, 399 and 446945, that multiplied together give a triangular number (178331055 = T₁₈₈₈₅).

The spelling of 399446945 in words is "three hundred ninety-nine million, four hundred forty-six thousand, nine hundred forty-five".