1221022121999 has 2 divisors, whose sum is σ = 1221022122000. Its totient is φ = 1221022121998.

The previous prime is 1221022121947. The next prime is 1221022122013. The reversal of 1221022121999 is 9991212201221.

It is a strong prime.

It is an emirp because it is prime and its reverse (9991212201221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221022121999 - 2²⁰ = 1221021073423 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221022121909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610511060999 + 610511061000.

It is an arithmetic number, because the mean of its divisors is an integer number (610511061000).

Almost surely, 2^{1221022121999} is an apocalyptic number.

1221022121999 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221022121999 is an equidigital number, since it uses as much as digits as its factorization.

1221022121999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 41.

The spelling of 1221022121999 in words is "one trillion, two hundred twenty-one billion, twenty-two million, one hundred twenty-one thousand, nine hundred ninety-nine".