21111111107 has 2 divisors, whose sum is σ = 21111111108. Its totient is φ = 21111111106.

The previous prime is 21111111061. The next prime is 21111111143. The reversal of 21111111107 is 70111111112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21111111107 - 2¹⁴ = 21111094723 is a prime.

It is not a weakly prime, because it can be changed into another prime (21111111167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555555553 + 10555555554.

It is an arithmetic number, because the mean of its divisors is an integer number (10555555554).

Almost surely, 2^21111111107 is an apocalyptic number.

21111111107 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111111107 is an equidigital number, since it uses as much as digits as its factorization.

21111111107 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14, while the sum is 17.

Adding to 21111111107 its reverse (70111111112), we get a palindrome (91222222219).

The spelling of 21111111107 in words is "twenty-one billion, one hundred eleven million, one hundred eleven thousand, one hundred seven".