1221111221017 has 2 divisors, whose sum is σ = 1221111221018. Its totient is φ = 1221111221016.

The previous prime is 1221111220999. The next prime is 1221111221021. The reversal of 1221111221017 is 7101221111221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1184039954496 + 37071266521 = 1088136^2 + 192539^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221111221017 - 2¹¹ = 1221111218969 is a prime.

It is a super-2 number, since 2×1221111221017² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1221111221717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610555610508 + 610555610509.

It is an arithmetic number, because the mean of its divisors is an integer number (610555610509).

Almost surely, 2^{1221111221017} is an apocalyptic number.

It is an amenable number.

1221111221017 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221111221017 is an equidigital number, since it uses as much as digits as its factorization.

1221111221017 is an odious number, because the sum of its binary digits is odd.

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

Adding to 1221111221017 its reverse (7101221111221), we get a palindrome (8322332332238).

The spelling of 1221111221017 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, two hundred twenty-one thousand, seventeen".