18120908911 has 4 divisors (see below), whose sum is σ = 20709610192. Its totient is φ = 15532207632.

The previous prime is 18120908903. The next prime is 18120908921. The reversal of 18120908911 is 11980902181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11980902181 = 19 ⋅630573799.

It is a cyclic number.

It is not a de Polignac number, because 18120908911 - 2³ = 18120908903 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18120908921) 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, 1294350630 + ... + 1294350643.

It is an arithmetic number, because the mean of its divisors is an integer number (5177402548).

Almost surely, 2^18120908911 is an apocalyptic number.

18120908911 is a deficient number, since it is larger than the sum of its proper divisors (2588701281).

18120908911 is an equidigital number, since it uses as much as digits as its factorization.

18120908911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2588701280.

The product of its (nonzero) digits is 10368, while the sum is 40.

The spelling of 18120908911 in words is "eighteen billion, one hundred twenty million, nine hundred eight thousand, nine hundred eleven".