21112100121017 has 2 divisors, whose sum is σ = 21112100121018. Its totient is φ = 21112100121016.

The previous prime is 21112100120981. The next prime is 21112100121109. The reversal of 21112100121017 is 71012100121112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16995863740816 + 4116236380201 = 4122604^2 + 2028851^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112100121017 - 2⁴⁰ = 20012588493241 is a prime.

It is a super-2 number, since 2×21112100121017² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21112100121017.

It is not a weakly prime, because it can be changed into another prime (21112100127017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556050060508 + 10556050060509.

It is an arithmetic number, because the mean of its divisors is an integer number (10556050060509).

Almost surely, 2^{21112100121017} is an apocalyptic number.

It is an amenable number.

21112100121017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112100121017 is an equidigital number, since it uses as much as digits as its factorization.

21112100121017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56, while the sum is 20.

Adding to 21112100121017 its reverse (71012100121112), we get a palindrome (92124200242129).

The spelling of 21112100121017 in words is "twenty-one trillion, one hundred twelve billion, one hundred million, one hundred twenty-one thousand, seventeen".