221211020221001 has 2 divisors, whose sum is σ = 221211020221002. Its totient is φ = 221211020221000.

The previous prime is 221211020220889. The next prime is 221211020221019. The reversal of 221211020221001 is 100122020112122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 190282740078601 + 30928280142400 = 13794301^2 + 5561320^2 .

It is a cyclic number.

It is not a de Polignac number, because 221211020221001 - 2²⁶ = 221210953112137 is a prime.

It is a super-2 number, since 2×221211020221001² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (221211020221801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110605510110500 + 110605510110501.

It is an arithmetic number, because the mean of its divisors is an integer number (110605510110501).

Almost surely, 2^{221211020221001} is an apocalyptic number.

It is an amenable number.

221211020221001 is a deficient number, since it is larger than the sum of its proper divisors (1).

221211020221001 is an equidigital number, since it uses as much as digits as its factorization.

221211020221001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 221211020221001 its reverse (100122020112122), we get a palindrome (321333040333123).

The spelling of 221211020221001 in words is "two hundred twenty-one trillion, two hundred eleven billion, twenty million, two hundred twenty-one thousand, one".