21101111113 has 2 divisors, whose sum is σ = 21101111114. Its totient is φ = 21101111112.

The previous prime is 21101111111. The next prime is 21101111149. The reversal of 21101111113 is 31111110112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20594546064 + 506565049 = 143508^2 + 22507^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101111113 - 2¹ = 21101111111 is a prime.

Together with 21101111111, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21101111093 and 21101111102.

It is not a weakly prime, because it can be changed into another prime (21101111111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550555556 + 10550555557.

It is an arithmetic number, because the mean of its divisors is an integer number (10550555557).

Almost surely, 2^21101111113 is an apocalyptic number.

It is an amenable number.

21101111113 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101111113 is an equidigital number, since it uses as much as digits as its factorization.

21101111113 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6, while the sum is 13.

Adding to 21101111113 its reverse (31111110112), we get a palindrome (52212221225).

The spelling of 21101111113 in words is "twenty-one billion, one hundred one million, one hundred eleven thousand, one hundred thirteen".