399321793 has 8 divisors (see below), whose sum is σ = 444868200. Its totient is φ = 355893888.

The previous prime is 399321787. The next prime is 399321859. The reversal of 399321793 is 397123993.

It can be written as a sum of positive squares in 4 ways, for example, as 9535744 + 389786049 = 3088^2 + 19743^2 .

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 399321793 - 2⁵ = 399321761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399321733) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 529228 + ... + 529981.

It is an arithmetic number, because the mean of its divisors is an integer number (55608525).

Almost surely, 2^399321793 is an apocalyptic number.

It is an amenable number.

399321793 is a deficient number, since it is larger than the sum of its proper divisors (45546407).

399321793 is a wasteful number, since it uses less digits than its factorization.

399321793 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1059251.

The product of its digits is 275562, while the sum is 46.

The square root of 399321793 is about 19983.0376319518. The cubic root of 399321793 is about 736.3896414971.

The spelling of 399321793 in words is "three hundred ninety-nine million, three hundred twenty-one thousand, seven hundred ninety-three".