121222021981 has 2 divisors, whose sum is σ = 121222021982. Its totient is φ = 121222021980.

The previous prime is 121222021871. The next prime is 121222022029. The reversal of 121222021981 is 189120222121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61260705081 + 59961316900 = 247509^2 + 244870^2 .

It is a cyclic number.

It is not a de Polignac number, because 121222021981 - 2⁷ = 121222021853 is a prime.

It is a super-2 number, since 2×121222021981² (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 (121222027981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60611010990 + 60611010991.

It is an arithmetic number, because the mean of its divisors is an integer number (60611010991).

Almost surely, 2^121222021981 is an apocalyptic number.

It is an amenable number.

121222021981 is a deficient number, since it is larger than the sum of its proper divisors (1).

121222021981 is an equidigital number, since it uses as much as digits as its factorization.

121222021981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 31.

The spelling of 121222021981 in words is "one hundred twenty-one billion, two hundred twenty-two million, twenty-one thousand, nine hundred eighty-one".