399539369 has 4 divisors (see below), whose sum is σ = 403418496. Its totient is φ = 395660244.

The previous prime is 399539347. The next prime is 399539401. The reversal of 399539369 is 963935993.

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 399539369 - 2¹² = 399535273 is a prime.

It is a super-2 number, since 2×399539369² = 319263414761836322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (399539269) 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, 1939409 + ... + 1939614.

It is an arithmetic number, because the mean of its divisors is an integer number (100854624).

Almost surely, 2^399539369 is an apocalyptic number.

It is an amenable number.

399539369 is a deficient number, since it is larger than the sum of its proper divisors (3879127).

399539369 is a wasteful number, since it uses less digits than its factorization.

399539369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3879126.

The product of its digits is 5314410, while the sum is 56.

The square root of 399539369 is about 19988.4809077629. The cubic root of 399539369 is about 736.5233612395.

The spelling of 399539369 in words is "three hundred ninety-nine million, five hundred thirty-nine thousand, three hundred sixty-nine".