21111100103 has 2 divisors, whose sum is σ = 21111100104. Its totient is φ = 21111100102.

The previous prime is 21111100097. The next prime is 21111100117. The reversal of 21111100103 is 30100111112.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21111100103 - 2¹⁸ = 21110837959 is a prime.

It is a super-2 number, since 2×21111100103² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111100133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555550051 + 10555550052.

It is an arithmetic number, because the mean of its divisors is an integer number (10555550052).

Almost surely, 2^21111100103 is an apocalyptic number.

21111100103 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111100103 is an equidigital number, since it uses as much as digits as its factorization.

21111100103 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6, while the sum is 11.

Adding to 21111100103 its reverse (30100111112), we get a palindrome (51211211215).

The spelling of 21111100103 in words is "twenty-one billion, one hundred eleven million, one hundred thousand, one hundred three".