2118191953 has 4 divisors (see below), whose sum is σ = 2229675760. Its totient is φ = 2006708148.

The previous prime is 2118191921. The next prime is 2118191989. The reversal of 2118191953 is 3591918112.

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 2118191953 - 2⁵ = 2118191921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2118191353) 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, 55741875 + ... + 55741912.

It is an arithmetic number, because the mean of its divisors is an integer number (557418940).

Almost surely, 2^2118191953 is an apocalyptic number.

It is an amenable number.

2118191953 is a deficient number, since it is larger than the sum of its proper divisors (111483807).

2118191953 is a wasteful number, since it uses less digits than its factorization.

2118191953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111483806.

The product of its digits is 19440, while the sum is 40.

The square root of 2118191953 is about 46023.8194090842. The cubic root of 2118191953 is about 1284.2663534629.

The spelling of 2118191953 in words is "two billion, one hundred eighteen million, one hundred ninety-one thousand, nine hundred fifty-three".