2118128761 has 4 divisors (see below), whose sum is σ = 2420718592. Its totient is φ = 1815538932.

The previous prime is 2118128741. The next prime is 2118128773. The reversal of 2118128761 is 1678218112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2118128761 - 2²¹ = 2116031609 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2118128761.

It is not an unprimeable number, because it can be changed into a prime (2118128731) 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, 151294905 + ... + 151294918.

It is an arithmetic number, because the mean of its divisors is an integer number (605179648).

Almost surely, 2^2118128761 is an apocalyptic number.

It is an amenable number.

2118128761 is a deficient number, since it is larger than the sum of its proper divisors (302589831).

2118128761 is an equidigital number, since it uses as much as digits as its factorization.

2118128761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302589830.

The product of its digits is 10752, while the sum is 37.

The square root of 2118128761 is about 46023.1328898848. The cubic root of 2118128761 is about 1284.2535821673.

The spelling of 2118128761 in words is "two billion, one hundred eighteen million, one hundred twenty-eight thousand, seven hundred sixty-one".