16987109 has 4 divisors (see below), whose sum is σ = 16996320. Its totient is φ = 16977900.

The previous prime is 16987067. The next prime is 16987111. The reversal of 16987109 is 90178961.

It is a happy number.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 90178961 = 101 ⋅892861.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16987109 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 (16987129) 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, 779 + ... + 5880.

It is an arithmetic number, because the mean of its divisors is an integer number (4249080).

Almost surely, 2^16987109 is an apocalyptic number.

It is an amenable number.

16987109 is a deficient number, since it is larger than the sum of its proper divisors (9211).

16987109 is an equidigital number, since it uses as much as digits as its factorization.

16987109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9210.

The product of its (nonzero) digits is 27216, while the sum is 41.

The square root of 16987109 is about 4121.5420657807. The cubic root of 16987109 is about 257.0631497075.

It can be divided in two parts, 169 and 87109, that added together give a palindrome (87278).

The spelling of 16987109 in words is "sixteen million, nine hundred eighty-seven thousand, one hundred nine".