9987915 has 48 divisors (see below), whose sum is σ = 18911232. Its totient is φ = 4487616.

The previous prime is 9987893. The next prime is 9987931. The reversal of 9987915 is 5197899.

9987915 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9987915 - 2⁶ = 9987851 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 78582 + ... + 78708.

It is an arithmetic number, because the mean of its divisors is an integer number (393984).

Almost surely, 2^9987915 is an apocalyptic number.

9987915 is a deficient number, since it is larger than the sum of its proper divisors (8923317).

9987915 is a wasteful number, since it uses less digits than its factorization.

9987915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256 (or 249 counting only the distinct ones).

The product of its digits is 204120, while the sum is 48.

The square root of 9987915 is about 3160.3662762408. The cubic root of 9987915 is about 215.3566462079.

The spelling of 9987915 in words is "nine million, nine hundred eighty-seven thousand, nine hundred fifteen".