1604318399 has 4 divisors (see below), whose sum is σ = 1613925264. Its totient is φ = 1594711536.

The previous prime is 1604318393. The next prime is 1604318411. The reversal of 1604318399 is 9938134061.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1604318399 - 2²⁴ = 1587541183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1604318393) 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, 4803182 + ... + 4803515.

It is an arithmetic number, because the mean of its divisors is an integer number (403481316).

Almost surely, 2^1604318399 is an apocalyptic number.

1604318399 is a deficient number, since it is larger than the sum of its proper divisors (9606865).

1604318399 is an equidigital number, since it uses as much as digits as its factorization.

1604318399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9606864.

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 1604318399 is about 40053.9436135819. The cubic root of 1604318399 is about 1170.6584062955.

The spelling of 1604318399 in words is "one billion, six hundred four million, three hundred eighteen thousand, three hundred ninety-nine".