20001101221217 has 2 divisors, whose sum is σ = 20001101221218. Its totient is φ = 20001101221216.

The previous prime is 20001101221193. The next prime is 20001101221247. The reversal of 20001101221217 is 71212210110002.

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., 19633902792256 + 367198428961 = 4431016^2 + 605969^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001101221217 - 2¹⁰ = 20001101220193 is a prime.

It is a super-2 number, since 2×20001101221217² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20001101221247) 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, 10000550610608 + 10000550610609.

It is an arithmetic number, because the mean of its divisors is an integer number (10000550610609).

Almost surely, 2^{20001101221217} is an apocalyptic number.

It is an amenable number.

20001101221217 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001101221217 is an equidigital number, since it uses as much as digits as its factorization.

20001101221217 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 20.

Adding to 20001101221217 its reverse (71212210110002), we get a palindrome (91213311331219).

The spelling of 20001101221217 in words is "twenty trillion, one billion, one hundred one million, two hundred twenty-one thousand, two hundred seventeen".