10515991 has 12 divisors (see below), whose sum is σ = 11157328. Its totient is φ = 9909504.

The previous prime is 10515977. The next prime is 10516003. The reversal of 10515991 is 19951501.

It is not a de Polignac number, because 10515991 - 2⁵ = 10515959 is a prime.

It is a super-2 number, since 2×10515991² = 221172133424162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10515931) 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 11 ways as a sum of consecutive naturals, for example, 54391 + ... + 54583.

Almost surely, 2^10515991 is an apocalyptic number.

10515991 is a deficient number, since it is larger than the sum of its proper divisors (641337).

10515991 is a wasteful number, since it uses less digits than its factorization.

10515991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342 (or 319 counting only the distinct ones).

The product of its (nonzero) digits is 2025, while the sum is 31.

The square root of 10515991 is about 3242.8368753300. The cubic root of 10515991 is about 219.0870639283.

The spelling of 10515991 in words is "ten million, five hundred fifteen thousand, nine hundred ninety-one".