221111111002021 has 2 divisors, whose sum is σ = 221111111002022. Its totient is φ = 221111111002020.

The previous prime is 221111111001983. The next prime is 221111111002043. The reversal of 221111111002021 is 120200111111122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 212026040920996 + 9085070081025 = 14561114^2 + 3014145^2 .

It is a cyclic number.

It is not a de Polignac number, because 221111111002021 - 2⁴⁵ = 185926738913189 is a prime.

It is a super-2 number, since 2×221111111002021² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 221111111001986 and 221111111002004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221111111002081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110555555501010 + 110555555501011.

It is an arithmetic number, because the mean of its divisors is an integer number (110555555501011).

Almost surely, 2^{221111111002021} is an apocalyptic number.

It is an amenable number.

221111111002021 is a deficient number, since it is larger than the sum of its proper divisors (1).

221111111002021 is an equidigital number, since it uses as much as digits as its factorization.

221111111002021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 221111111002021 its reverse (120200111111122), we get a palindrome (341311222113143).

The spelling of 221111111002021 in words is "two hundred twenty-one trillion, one hundred eleven billion, one hundred eleven million, two thousand, twenty-one".