221020221021121 has 2 divisors, whose sum is σ = 221020221021122. Its totient is φ = 221020221021120.

The previous prime is 221020221021101. The next prime is 221020221021137. The reversal of 221020221021121 is 121120122020122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 154431944514225 + 66588276506896 = 12427065^2 + 8160164^2 .

It is a cyclic number.

It is not a de Polignac number, because 221020221021121 - 2¹⁵ = 221020220988353 is a prime.

It is not a weakly prime, because it can be changed into another prime (221020221021101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110510110510560 + 110510110510561.

It is an arithmetic number, because the mean of its divisors is an integer number (110510110510561).

Almost surely, 2^{221020221021121} is an apocalyptic number.

It is an amenable number.

221020221021121 is a deficient number, since it is larger than the sum of its proper divisors (1).

221020221021121 is an equidigital number, since it uses as much as digits as its factorization.

221020221021121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 221020221021121 its reverse (121120122020122), we get a palindrome (342140343041243).

Subtracting from 221020221021121 its reverse (121120122020122), we obtain a palindrome (99900099000999).

The spelling of 221020221021121 in words is "two hundred twenty-one trillion, twenty billion, two hundred twenty-one million, twenty-one thousand, one hundred twenty-one".