121221122021 has 2 divisors, whose sum is σ = 121221122022. Its totient is φ = 121221122020.

The previous prime is 121221121997. The next prime is 121221122027. The reversal of 121221122021 is 120221122121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 105816837025 + 15404284996 = 325295^2 + 124114^2 .

It is a cyclic number.

It is not a de Polignac number, because 121221122021 - 2¹⁰ = 121221120997 is a prime.

It is a super-2 number, since 2×121221122021² (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 (121221122027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60610561010 + 60610561011.

It is an arithmetic number, because the mean of its divisors is an integer number (60610561011).

Almost surely, 2^121221122021 is an apocalyptic number.

It is an amenable number.

121221122021 is a deficient number, since it is larger than the sum of its proper divisors (1).

121221122021 is an equidigital number, since it uses as much as digits as its factorization.

121221122021 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 121221122021 its reverse (120221122121), we get a palindrome (241442244142).

The spelling of 121221122021 in words is "one hundred twenty-one billion, two hundred twenty-one million, one hundred twenty-two thousand, twenty-one".