1001020011221 has 2 divisors, whose sum is σ = 1001020011222. Its totient is φ = 1001020011220.

The previous prime is 1001020011203. The next prime is 1001020011239. The reversal of 1001020011221 is 1221100201001.

It is a balanced prime because it is at equal distance from previous prime (1001020011203) and next prime (1001020011239).

It can be written as a sum of positive squares in only one way, i.e., 1000270018225 + 749992996 = 1000135^2 + 27386^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001020011221 - 2⁶ = 1001020011157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1001020011281) 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, 500510005610 + 500510005611.

It is an arithmetic number, because the mean of its divisors is an integer number (500510005611).

Almost surely, 2^{1001020011221} is an apocalyptic number.

It is an amenable number.

1001020011221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001020011221 is an equidigital number, since it uses as much as digits as its factorization.

1001020011221 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 11.

Adding to 1001020011221 its reverse (1221100201001), we get a palindrome (2222120212222).

The spelling of 1001020011221 in words is "one trillion, one billion, twenty million, eleven thousand, two hundred twenty-one".