2091815 has 16 divisors (see below), whose sum is σ = 2781216. Its totient is φ = 1497600.

The previous prime is 2091809. The next prime is 2091839. The reversal of 2091815 is 5181902.

It is a happy number.

It is not a de Polignac number, because 2091815 - 2¹⁰ = 2090791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3755 + ... + 4275.

It is an arithmetic number, because the mean of its divisors is an integer number (173826).

2^2091815 is an apocalyptic number.

2091815 is a deficient number, since it is larger than the sum of its proper divisors (689401).

2091815 is a wasteful number, since it uses less digits than its factorization.

2091815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 610.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 2091815 is about 1446.3108241315. The cubic root of 2091815 is about 127.8913262176.

The spelling of 2091815 in words is "two million, ninety-one thousand, eight hundred fifteen".