1211022201721 has 2 divisors, whose sum is σ = 1211022201722. Its totient is φ = 1211022201720.

The previous prime is 1211022201679. The next prime is 1211022201733. The reversal of 1211022201721 is 1271022201121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1187533267600 + 23488934121 = 1089740^2 + 153261^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211022201721 - 2¹³ = 1211022193529 is a prime.

It is a super-2 number, since 2×1211022201721² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1211022201692 and 1211022201701.

It is not a weakly prime, because it can be changed into another prime (1211022201791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605511100860 + 605511100861.

It is an arithmetic number, because the mean of its divisors is an integer number (605511100861).

Almost surely, 2^{1211022201721} is an apocalyptic number.

It is an amenable number.

1211022201721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211022201721 is an equidigital number, since it uses as much as digits as its factorization.

1211022201721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 224, while the sum is 22.

Adding to 1211022201721 its reverse (1271022201121), we get a palindrome (2482044402842).

The spelling of 1211022201721 in words is "one trillion, two hundred eleven billion, twenty-two million, two hundred one thousand, seven hundred twenty-one".