21220044112717 has 2 divisors, whose sum is σ = 21220044112718. Its totient is φ = 21220044112716.

The previous prime is 21220044112697. The next prime is 21220044112721. The reversal of 21220044112717 is 71721144002212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12005261749321 + 9214782363396 = 3464861^2 + 3035586^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21220044112717 is a prime.

It is a super-2 number, since 2×21220044112717² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220044712717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610022056358 + 10610022056359.

It is an arithmetic number, because the mean of its divisors is an integer number (10610022056359).

Almost surely, 2^{21220044112717} is an apocalyptic number.

It is an amenable number.

21220044112717 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220044112717 is an equidigital number, since it uses as much as digits as its factorization.

21220044112717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12544, while the sum is 34.

Adding to 21220044112717 its reverse (71721144002212), we get a palindrome (92941188114929).

The spelling of 21220044112717 in words is "twenty-one trillion, two hundred twenty billion, forty-four million, one hundred twelve thousand, seven hundred seventeen".