20111101111091 has 2 divisors, whose sum is σ = 20111101111092. Its totient is φ = 20111101111090.

The previous prime is 20111101111001. The next prime is 20111101111111. The reversal of 20111101111091 is 19011110111102.

It is a happy number.

It is an a-pointer prime, because the next prime (20111101111111) can be obtained adding 20111101111091 to its sum of digits (20).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20111101111091 - 2²² = 20111096916787 is a prime.

It is not a weakly prime, because it can be changed into another prime (20111101111001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10055550555545 + 10055550555546.

It is an arithmetic number, because the mean of its divisors is an integer number (10055550555546).

Almost surely, 2^{20111101111091} is an apocalyptic number.

20111101111091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20111101111091 is an equidigital number, since it uses as much as digits as its factorization.

20111101111091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18, while the sum is 20.

Adding to 20111101111091 its reverse (19011110111102), we get a palindrome (39122211222193).

The spelling of 20111101111091 in words is "twenty trillion, one hundred eleven billion, one hundred one million, one hundred eleven thousand, ninety-one".