18021266113 has 4 divisors (see below), whose sum is σ = 18044947908. Its totient is φ = 17997584320.

The previous prime is 18021266111. The next prime is 18021266119. The reversal of 18021266113 is 31166212081.

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 8091542209 + 9929723904 = 89953^2 + 99648^2 .

It is a cyclic number.

It is not a de Polignac number, because 18021266113 - 2¹ = 18021266111 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18021266111) 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, 11839756 + ... + 11841277.

It is an arithmetic number, because the mean of its divisors is an integer number (4511236977).

Almost surely, 2^18021266113 is an apocalyptic number.

It is an amenable number.

18021266113 is a deficient number, since it is larger than the sum of its proper divisors (23681795).

18021266113 is an equidigital number, since it uses as much as digits as its factorization.

18021266113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23681794.

The product of its (nonzero) digits is 3456, while the sum is 31.

Adding to 18021266113 its reverse (31166212081), we get a palindrome (49187478194).

The spelling of 18021266113 in words is "eighteen billion, twenty-one million, two hundred sixty-six thousand, one hundred thirteen".