2217166345021 has 2 divisors, whose sum is σ = 2217166345022. Its totient is φ = 2217166345020.

The previous prime is 2217166344971. The next prime is 2217166345061. The reversal of 2217166345021 is 1205436617122.

It is an a-pointer prime, because the next prime (2217166345061) can be obtained adding 2217166345021 to its sum of digits (40).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2060548282521 + 156618062500 = 1435461^2 + 395750^2 .

It is a cyclic number.

It is not a de Polignac number, because 2217166345021 - 2¹³ = 2217166336829 is a prime.

It is a super-2 number, since 2×2217166345021² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2217166345061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1108583172510 + 1108583172511.

It is an arithmetic number, because the mean of its divisors is an integer number (1108583172511).

Almost surely, 2^{2217166345021} is an apocalyptic number.

It is an amenable number.

2217166345021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2217166345021 is an equidigital number, since it uses as much as digits as its factorization.

2217166345021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120960, while the sum is 40.

The spelling of 2217166345021 in words is "two trillion, two hundred seventeen billion, one hundred sixty-six million, three hundred forty-five thousand, twenty-one".