21111102221017 has 2 divisors, whose sum is σ = 21111102221018. Its totient is φ = 21111102221016.

The previous prime is 21111102220997. The next prime is 21111102221059. The reversal of 21111102221017 is 71012220111112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18438985636096 + 2672116584921 = 4294064^2 + 1634661^2 .

It is a cyclic number.

It is not a de Polignac number, because 21111102221017 - 2³¹ = 21108954737369 is a prime.

It is not a weakly prime, because it can be changed into another prime (21111102221087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555551110508 + 10555551110509.

It is an arithmetic number, because the mean of its divisors is an integer number (10555551110509).

Almost surely, 2^{21111102221017} is an apocalyptic number.

It is an amenable number.

21111102221017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111102221017 is an equidigital number, since it uses as much as digits as its factorization.

21111102221017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 22.

Adding to 21111102221017 its reverse (71012220111112), we get a palindrome (92123322332129).

The spelling of 21111102221017 in words is "twenty-one trillion, one hundred eleven billion, one hundred two million, two hundred twenty-one thousand, seventeen".