21111153103 has 2 divisors, whose sum is σ = 21111153104. Its totient is φ = 21111153102.

The previous prime is 21111153013. The next prime is 21111153131. The reversal of 21111153103 is 30135111112.

Together with previous prime (21111153013) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21111153103 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111157103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555576551 + 10555576552.

It is an arithmetic number, because the mean of its divisors is an integer number (10555576552).

Almost surely, 2^21111153103 is an apocalyptic number.

21111153103 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111153103 is an equidigital number, since it uses as much as digits as its factorization.

21111153103 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90, while the sum is 19.

Adding to 21111153103 its reverse (30135111112), we get a palindrome (51246264215).

The spelling of 21111153103 in words is "twenty-one billion, one hundred eleven million, one hundred fifty-three thousand, one hundred three".