8991515 has 16 divisors (see below), whose sum is σ = 11893728. Its totient is φ = 6483456.

The previous prime is 8991449. The next prime is 8991517. The reversal of 8991515 is 5151998.

8991515 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 8991515 - 2¹⁶ = 8925979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8991517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1187 + ... + 4403.

It is an arithmetic number, because the mean of its divisors is an integer number (743358).

Almost surely, 2^8991515 is an apocalyptic number.

8991515 is a deficient number, since it is larger than the sum of its proper divisors (2902213).

8991515 is a wasteful number, since it uses less digits than its factorization.

8991515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3278.

The product of its digits is 16200, while the sum is 38.

The square root of 8991515 is about 2998.5854998649. The cubic root of 8991515 is about 207.9429931916.

The spelling of 8991515 in words is "eight million, nine hundred ninety-one thousand, five hundred fifteen".