2117661115 has 4 divisors (see below), whose sum is σ = 2541193344. Its totient is φ = 1694128888.

The previous prime is 2117661103. The next prime is 2117661167. The reversal of 2117661115 is 5111667112.

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 2117661115 - 2¹⁷ = 2117530043 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 211766107 + ... + 211766116.

It is an arithmetic number, because the mean of its divisors is an integer number (635298336).

Almost surely, 2^2117661115 is an apocalyptic number.

2117661115 is a deficient number, since it is larger than the sum of its proper divisors (423532229).

2117661115 is an equidigital number, since it uses as much as digits as its factorization.

2117661115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423532228.

The product of its digits is 2520, while the sum is 31.

The square root of 2117661115 is about 46018.0520556879. The cubic root of 2117661115 is about 1284.1590615908.

The spelling of 2117661115 in words is "two billion, one hundred seventeen million, six hundred sixty-one thousand, one hundred fifteen".