21500111321093 has 2 divisors, whose sum is σ = 21500111321094. Its totient is φ = 21500111321092.

The previous prime is 21500111321047. The next prime is 21500111321113. The reversal of 21500111321093 is 39012311100512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20163539486689 + 1336571834404 = 4490383^2 + 1156102^2 .

It is a cyclic number.

It is not a de Polignac number, because 21500111321093 - 2²⁰ = 21500110272517 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21500111321393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10750055660546 + 10750055660547.

It is an arithmetic number, because the mean of its divisors is an integer number (10750055660547).

Almost surely, 2^{21500111321093} is an apocalyptic number.

It is an amenable number.

21500111321093 is a deficient number, since it is larger than the sum of its proper divisors (1).

21500111321093 is an equidigital number, since it uses as much as digits as its factorization.

21500111321093 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1620, while the sum is 29.

The spelling of 21500111321093 in words is "twenty-one trillion, five hundred billion, one hundred eleven million, three hundred twenty-one thousand, ninety-three".