16317985 has 4 divisors (see below), whose sum is σ = 19581588. Its totient is φ = 13054384.

The previous prime is 16317967. The next prime is 16317989. The reversal of 16317985 is 58971361.

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

It can be written as a sum of positive squares in 2 ways, for example, as 7750656 + 8567329 = 2784^2 + 2927^2 .

It is a cyclic number.

It is not a de Polignac number, because 16317985 - 2⁵ = 16317953 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16317989) 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, 1631794 + ... + 1631803.

It is an arithmetic number, because the mean of its divisors is an integer number (4895397).

Almost surely, 2^16317985 is an apocalyptic number.

It is an amenable number.

16317985 is a deficient number, since it is larger than the sum of its proper divisors (3263603).

16317985 is an equidigital number, since it uses as much as digits as its factorization.

16317985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3263602.

The product of its digits is 45360, while the sum is 40.

The square root of 16317985 is about 4039.5525742339. The cubic root of 16317985 is about 253.6425884301.

The spelling of 16317985 in words is "sixteen million, three hundred seventeen thousand, nine hundred eighty-five".