221211122021 has 2 divisors, whose sum is σ = 221211122022. Its totient is φ = 221211122020.

The previous prime is 221211122017. The next prime is 221211122053. The reversal of 221211122021 is 120221112122.

221211122021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 125553292225 + 95657829796 = 354335^2 + 309286^2 .

It is a cyclic number.

It is not a de Polignac number, because 221211122021 - 2² = 221211122017 is a prime.

It is a super-2 number, since 2×221211122021² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221211124021) 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, 110605561010 + 110605561011.

It is an arithmetic number, because the mean of its divisors is an integer number (110605561011).

Almost surely, 2^221211122021 is an apocalyptic number.

It is an amenable number.

221211122021 is a deficient number, since it is larger than the sum of its proper divisors (1).

221211122021 is an equidigital number, since it uses as much as digits as its factorization.

221211122021 is an odious number, because the sum of its binary digits is odd.

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

Adding to 221211122021 its reverse (120221112122), we get a palindrome (341432234143).

The spelling of 221211122021 in words is "two hundred twenty-one billion, two hundred eleven million, one hundred twenty-two thousand, twenty-one".