121220221021 has 2 divisors, whose sum is σ = 121220221022. Its totient is φ = 121220221020.

The previous prime is 121220220991. The next prime is 121220221043. The reversal of 121220221021 is 120122022121.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 121096344121 + 123876900 = 347989^2 + 11130^2 .

It is a cyclic number.

It is not a de Polignac number, because 121220221021 - 2¹³ = 121220212829 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121220220986 and 121220221004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121220221051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60610110510 + 60610110511.

It is an arithmetic number, because the mean of its divisors is an integer number (60610110511).

Almost surely, 2^121220221021 is an apocalyptic number.

It is an amenable number.

121220221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

121220221021 is an equidigital number, since it uses as much as digits as its factorization.

121220221021 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 16.

Adding to 121220221021 its reverse (120122022121), we get a palindrome (241342243142).

The spelling of 121220221021 in words is "one hundred twenty-one billion, two hundred twenty million, two hundred twenty-one thousand, twenty-one".