1001220121999 has 2 divisors, whose sum is σ = 1001220122000. Its totient is φ = 1001220121998.

The previous prime is 1001220121991. The next prime is 1001220122033. The reversal of 1001220121999 is 9991210221001.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1001220121999 - 2³ = 1001220121991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1001220121991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500610060999 + 500610061000.

It is an arithmetic number, because the mean of its divisors is an integer number (500610061000).

Almost surely, 2^{1001220121999} is an apocalyptic number.

1001220121999 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001220121999 is an equidigital number, since it uses as much as digits as its factorization.

1001220121999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 37.

The spelling of 1001220121999 in words is "one trillion, one billion, two hundred twenty million, one hundred twenty-one thousand, nine hundred ninety-nine".