1221111103217 has 2 divisors, whose sum is σ = 1221111103218. Its totient is φ = 1221111103216.

The previous prime is 1221111103187. The next prime is 1221111103253. The reversal of 1221111103217 is 7123011111221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 825873818176 + 395237285041 = 908776^2 + 628679^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221111103217 - 2²⁰ = 1221110054641 is a prime.

It is a super-2 number, since 2×1221111103217² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221111103192 and 1221111103201.

It is not a weakly prime, because it can be changed into another prime (1221111103297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610555551608 + 610555551609.

It is an arithmetic number, because the mean of its divisors is an integer number (610555551609).

Almost surely, 2^{1221111103217} is an apocalyptic number.

It is an amenable number.

1221111103217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221111103217 is an equidigital number, since it uses as much as digits as its factorization.

1221111103217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 168, while the sum is 23.

Adding to 1221111103217 its reverse (7123011111221), we get a palindrome (8344122214438).

The spelling of 1221111103217 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, one hundred three thousand, two hundred seventeen".