1020221100991 has 2 divisors, whose sum is σ = 1020221100992. Its totient is φ = 1020221100990.

The previous prime is 1020221100971. The next prime is 1020221101001. The reversal of 1020221100991 is 1990011220201.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1020221100991 - 2⁵ = 1020221100959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1020221100931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510110550495 + 510110550496.

It is an arithmetic number, because the mean of its divisors is an integer number (510110550496).

Almost surely, 2^{1020221100991} is an apocalyptic number.

1020221100991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020221100991 is an equidigital number, since it uses as much as digits as its factorization.

1020221100991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 28.

The spelling of 1020221100991 in words is "one trillion, twenty billion, two hundred twenty-one million, one hundred thousand, nine hundred ninety-one".