16990309 has 12 divisors (see below), whose sum is σ = 19853100. Its totient is φ = 14497728.

The previous prime is 16990291. The next prime is 16990319. The reversal of 16990309 is 90309961.

It can be written as a sum of positive squares in 2 ways, for example, as 6890625 + 10099684 = 2625^2 + 3178^2 .

It is a de Polignac number, because none of the positive numbers 2^k-16990309 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 (16990319) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12537 + ... + 13825.

It is an arithmetic number, because the mean of its divisors is an integer number (1654425).

Almost surely, 2^16990309 is an apocalyptic number.

It is an amenable number.

16990309 is a deficient number, since it is larger than the sum of its proper divisors (2862791).

16990309 is a wasteful number, since it uses less digits than its factorization.

16990309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1572 (or 1565 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 37.

The square root of 16990309 is about 4121.9302517146. The cubic root of 16990309 is about 257.0792903867.

The spelling of 16990309 in words is "sixteen million, nine hundred ninety thousand, three hundred nine".