11001010991 has 2 divisors, whose sum is σ = 11001010992. Its totient is φ = 11001010990.

The previous prime is 11001010949. The next prime is 11001011027. The reversal of 11001010991 is 19901010011.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11001010991 - 2¹⁰ = 11001009967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11001010091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5500505495 + 5500505496.

It is an arithmetic number, because the mean of its divisors is an integer number (5500505496).

Almost surely, 2^11001010991 is an apocalyptic number.

11001010991 is a deficient number, since it is larger than the sum of its proper divisors (1).

11001010991 is an equidigital number, since it uses as much as digits as its factorization.

11001010991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81, while the sum is 23.

The spelling of 11001010991 in words is "eleven billion, one million, ten thousand, nine hundred ninety-one".