18112016721 has 16 divisors (see below), whose sum is σ = 24306345536. Its totient is φ = 11996237376.

The previous prime is 18112016707. The next prime is 18112016731. The reversal of 18112016721 is 12761021181.

It is not a de Polignac number, because 18112016721 - 2¹⁴ = 18112000337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18112016731) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1879311 + ... + 1888923.

It is an arithmetic number, because the mean of its divisors is an integer number (1519146596).

Almost surely, 2^18112016721 is an apocalyptic number.

It is an amenable number.

18112016721 is a deficient number, since it is larger than the sum of its proper divisors (6194328815).

18112016721 is a wasteful number, since it uses less digits than its factorization.

18112016721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13632.

The product of its (nonzero) digits is 1344, while the sum is 30.

The spelling of 18112016721 in words is "eighteen billion, one hundred twelve million, sixteen thousand, seven hundred twenty-one".