108987665 has 4 divisors (see below), whose sum is σ = 130785204. Its totient is φ = 87190128.

The previous prime is 108987653. The next prime is 108987701. The reversal of 108987665 is 566789801.

Added to its reverse (566789801) it gives a triangular number (675777466 = T₃₆₇₆₃).

It is a happy number.

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 56685841 + 52301824 = 7529^2 + 7232^2 .

It is a cyclic number.

It is not a de Polignac number, because 108987665 - 2⁶ = 108987601 is a prime.

It is a super-2 number, since 2×108987665² = 23756622244304450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10898762 + ... + 10898771.

It is an arithmetic number, because the mean of its divisors is an integer number (32696301).

Almost surely, 2^108987665 is an apocalyptic number.

It is an amenable number.

108987665 is a deficient number, since it is larger than the sum of its proper divisors (21797539).

108987665 is an equidigital number, since it uses as much as digits as its factorization.

108987665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21797538.

The product of its (nonzero) digits is 725760, while the sum is 50.

The square root of 108987665 is about 10439.7157528354. The cubic root of 108987665 is about 477.6675983042.

Adding to 108987665 its reverse (566789801), we get a triangular number (675777466 = T₃₆₇₆₃).

The spelling of 108987665 in words is "one hundred eight million, nine hundred eighty-seven thousand, six hundred sixty-five".