399383609 has 2 divisors, whose sum is σ = 399383610. Its totient is φ = 399383608.

The previous prime is 399383597. The next prime is 399383617. The reversal of 399383609 is 906383993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 324180025 + 75203584 = 18005^2 + 8672^2 .

It is a cyclic number.

It is not a de Polignac number, because 399383609 - 2⁸ = 399383353 is a prime.

It is not a weakly prime, because it can be changed into another prime (399383909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199691804 + 199691805.

It is an arithmetic number, because the mean of its divisors is an integer number (199691805).

Almost surely, 2^399383609 is an apocalyptic number.

It is an amenable number.

399383609 is a deficient number, since it is larger than the sum of its proper divisors (1).

399383609 is an equidigital number, since it uses as much as digits as its factorization.

399383609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 944784, while the sum is 50.

The square root of 399383609 is about 19984.5842838924. The cubic root of 399383609 is about 736.4276378484.

The spelling of 399383609 in words is "three hundred ninety-nine million, three hundred eighty-three thousand, six hundred nine".