2115831 has 4 divisors (see below), whose sum is σ = 2821112. Its totient is φ = 1410552.

The previous prime is 2115829. The next prime is 2115847. The reversal of 2115831 is 1385112.

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

It is not a de Polignac number, because 2115831 - 2¹ = 2115829 is a prime.

It is a super-2 number, since 2×2115831² = 8953481641122, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2115798 and 2115807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2115131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 352636 + ... + 352641.

It is an arithmetic number, because the mean of its divisors is an integer number (705278).

2^2115831 is an apocalyptic number.

2115831 is a deficient number, since it is larger than the sum of its proper divisors (705281).

2115831 is an equidigital number, since it uses as much as digits as its factorization.

2115831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705280.

The product of its digits is 240, while the sum is 21.

The square root of 2115831 is about 1454.5896328518. The cubic root of 2115831 is about 128.3789025031.

The spelling of 2115831 in words is "two million, one hundred fifteen thousand, eight hundred thirty-one".