21118110113 has 2 divisors, whose sum is σ = 21118110114. Its totient is φ = 21118110112.

The previous prime is 21118110109. The next prime is 21118110127. The reversal of 21118110113 is 31101181112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20434130704 + 683979409 = 142948^2 + 26153^2 .

It is a cyclic number.

It is not a de Polignac number, because 21118110113 - 2² = 21118110109 is a prime.

It is not a weakly prime, because it can be changed into another prime (21118110103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10559055056 + 10559055057.

It is an arithmetic number, because the mean of its divisors is an integer number (10559055057).

Almost surely, 2^21118110113 is an apocalyptic number.

It is an amenable number.

21118110113 is a deficient number, since it is larger than the sum of its proper divisors (1).

21118110113 is an equidigital number, since it uses as much as digits as its factorization.

21118110113 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 20.

Adding to 21118110113 its reverse (31101181112), we get a palindrome (52219291225).

The spelling of 21118110113 in words is "twenty-one billion, one hundred eighteen million, one hundred ten thousand, one hundred thirteen".