16808987 has 4 divisors (see below), whose sum is σ = 18102000. Its totient is φ = 15515976.

The previous prime is 16808983. The next prime is 16808993. The reversal of 16808987 is 78980861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78980861 = 17 ⋅4645933.

It is a cyclic number.

It is not a de Polignac number, because 16808987 - 2² = 16808983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16808983) 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, 646487 + ... + 646512.

It is an arithmetic number, because the mean of its divisors is an integer number (4525500).

Almost surely, 2^16808987 is an apocalyptic number.

16808987 is a deficient number, since it is larger than the sum of its proper divisors (1293013).

16808987 is a wasteful number, since it uses less digits than its factorization.

16808987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1293012.

The product of its (nonzero) digits is 193536, while the sum is 47.

The square root of 16808987 is about 4099.8764615534. The cubic root of 16808987 is about 256.1614937651.

The spelling of 16808987 in words is "sixteen million, eight hundred eight thousand, nine hundred eighty-seven".