399625321 has 4 divisors (see below), whose sum is σ = 400039552. Its totient is φ = 399211092.

The previous prime is 399625229. The next prime is 399625333. The reversal of 399625321 is 123526993.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 399625321 - 2⁹ = 399624809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399625921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 205665 + ... + 207598.

It is an arithmetic number, because the mean of its divisors is an integer number (100009888).

Almost surely, 2^399625321 is an apocalyptic number.

It is an amenable number.

399625321 is a deficient number, since it is larger than the sum of its proper divisors (414231).

399625321 is an equidigital number, since it uses as much as digits as its factorization.

399625321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414230.

The product of its digits is 87480, while the sum is 40.

The square root of 399625321 is about 19990.6308304666. The cubic root of 399625321 is about 736.5761729871.

The spelling of 399625321 in words is "three hundred ninety-nine million, six hundred twenty-five thousand, three hundred twenty-one".