2115665243 has 4 divisors (see below), whose sum is σ = 2116010160. Its totient is φ = 2115320328.

The previous prime is 2115665239. The next prime is 2115665273. The reversal of 2115665243 is 3425665112.

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 2115665243 - 2² = 2115665239 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2115665273) 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, 163088 + ... + 175581.

It is an arithmetic number, because the mean of its divisors is an integer number (529002540).

Almost surely, 2^2115665243 is an apocalyptic number.

2115665243 is a deficient number, since it is larger than the sum of its proper divisors (344917).

2115665243 is an equidigital number, since it uses as much as digits as its factorization.

2115665243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344916.

The product of its digits is 43200, while the sum is 35.

The square root of 2115665243 is about 45996.3611930335. The cubic root of 2115665243 is about 1283.7554995787.

The spelling of 2115665243 in words is "two billion, one hundred fifteen million, six hundred sixty-five thousand, two hundred forty-three".