1000011000991 has 2 divisors, whose sum is σ = 1000011000992. Its totient is φ = 1000011000990.

The previous prime is 1000011000931. The next prime is 1000011001009. The reversal of 1000011000991 is 1990001100001.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1000011000991 - 2¹⁵ = 1000010968223 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1000011000931) 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, 500005500495 + 500005500496.

It is an arithmetic number, because the mean of its divisors is an integer number (500005500496).

Almost surely, 2^{1000011000991} is an apocalyptic number.

1000011000991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1000011000991 is an equidigital number, since it uses as much as digits as its factorization.

1000011000991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81, while the sum is 22.

Adding to 1000011000991 its reverse (1990001100001), we get a palindrome (2990012100992).

The spelling of 1000011000991 in words is "one trillion, eleven million, nine hundred ninety-one", and thus it is an aban number.