121221020200121 has 2 divisors, whose sum is σ = 121221020200122. Its totient is φ = 121221020200120.

The previous prime is 121221020200099. The next prime is 121221020200127. The reversal of 121221020200121 is 121002020122121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 117262671206521 + 3958348993600 = 10828789^2 + 1989560^2 .

It is a cyclic number.

It is not a de Polignac number, because 121221020200121 - 2¹⁸ = 121221019937977 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121221020200121.

It is not a weakly prime, because it can be changed into another prime (121221020200127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60610510100060 + 60610510100061.

It is an arithmetic number, because the mean of its divisors is an integer number (60610510100061).

Almost surely, 2^{121221020200121} is an apocalyptic number.

It is an amenable number.

121221020200121 is a deficient number, since it is larger than the sum of its proper divisors (1).

121221020200121 is an equidigital number, since it uses as much as digits as its factorization.

121221020200121 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 121221020200121 its reverse (121002020122121), we get a palindrome (242223040322242).

The spelling of 121221020200121 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, twenty million, two hundred thousand, one hundred twenty-one".