991080515 has 4 divisors (see below), whose sum is σ = 1189296624. Its totient is φ = 792864408.

The previous prime is 991080491. The next prime is 991080533. The reversal of 991080515 is 515080199.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 991080515 - 2¹⁰ = 991079491 is a prime.

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, 99108047 + ... + 99108056.

It is an arithmetic number, because the mean of its divisors is an integer number (297324156).

Almost surely, 2^991080515 is an apocalyptic number.

991080515 is a deficient number, since it is larger than the sum of its proper divisors (198216109).

991080515 is a wasteful number, since it uses less digits than its factorization.

991080515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198216108.

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

The square root of 991080515 is about 31481.4312730536. The cubic root of 991080515 is about 997.0179545778.

The spelling of 991080515 in words is "nine hundred ninety-one million, eighty thousand, five hundred fifteen".