1001221111201 has 2 divisors, whose sum is σ = 1001221111202. Its totient is φ = 1001221111200.

The previous prime is 1001221111199. The next prime is 1001221111207. The reversal of 1001221111201 is 1021111221001.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 668222867601 + 332998243600 = 817449^2 + 577060^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001221111201 - 2¹ = 1001221111199 is a prime.

Together with 1001221111199, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1001221111207) 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, 500610555600 + 500610555601.

It is an arithmetic number, because the mean of its divisors is an integer number (500610555601).

Almost surely, 2^{1001221111201} is an apocalyptic number.

It is an amenable number.

1001221111201 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001221111201 is an equidigital number, since it uses as much as digits as its factorization.

1001221111201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1001221111201 its reverse (1021111221001), we get a palindrome (2022332332202).

The spelling of 1001221111201 in words is "one trillion, one billion, two hundred twenty-one million, one hundred eleven thousand, two hundred one".