2118215841517 has 4 divisors (see below), whose sum is σ = 2118811351356. Its totient is φ = 2117620331680.

The previous prime is 2118215841509. The next prime is 2118215841523. The reversal of 2118215841517 is 7151485128112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 175275358281 + 1942940483236 = 418659^2 + 1393894^2 .

It is a cyclic number.

It is not a de Polignac number, because 2118215841517 - 2³ = 2118215841509 is a prime.

It is a super-2 number, since 2×2118215841517² (a number of 25 digits) 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 (2118215841017) 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, 297749584 + ... + 297756697.

It is an arithmetic number, because the mean of its divisors is an integer number (529702837839).

Almost surely, 2^{2118215841517} is an apocalyptic number.

It is an amenable number.

2118215841517 is a deficient number, since it is larger than the sum of its proper divisors (595509839).

2118215841517 is an equidigital number, since it uses as much as digits as its factorization.

2118215841517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 595509838.

The product of its digits is 179200, while the sum is 46.

The spelling of 2118215841517 in words is "two trillion, one hundred eighteen billion, two hundred fifteen million, eight hundred forty-one thousand, five hundred seventeen".