121220111220217 has 2 divisors, whose sum is σ = 121220111220218. Its totient is φ = 121220111220216.

The previous prime is 121220111220199. The next prime is 121220111220227. The reversal of 121220111220217 is 712022111022121.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72144145800441 + 49075965419776 = 8493771^2 + 7005424^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121220111220217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121220111220191 and 121220111220200.

It is not a weakly prime, because it can be changed into another prime (121220111220227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60610055610108 + 60610055610109.

It is an arithmetic number, because the mean of its divisors is an integer number (60610055610109).

Almost surely, 2^{121220111220217} is an apocalyptic number.

It is an amenable number.

121220111220217 is a deficient number, since it is larger than the sum of its proper divisors (1).

121220111220217 is an equidigital number, since it uses as much as digits as its factorization.

121220111220217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 448, while the sum is 25.

Adding to 121220111220217 its reverse (712022111022121), we get a palindrome (833242222242338).

The spelling of 121220111220217 in words is "one hundred twenty-one trillion, two hundred twenty billion, one hundred eleven million, two hundred twenty thousand, two hundred seventeen".