21112122091 has 2 divisors, whose sum is σ = 21112122092. Its totient is φ = 21112122090.

The previous prime is 21112122079. The next prime is 21112122127. The reversal of 21112122091 is 19022121112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21112122091 - 2⁷ = 21112121963 is a prime.

It is not a weakly prime, because it can be changed into another prime (21112122191) 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, 10556061045 + 10556061046.

It is an arithmetic number, because the mean of its divisors is an integer number (10556061046).

Almost surely, 2^21112122091 is an apocalyptic number.

21112122091 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112122091 is an equidigital number, since it uses as much as digits as its factorization.

21112122091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 21112122091 in words is "twenty-one billion, one hundred twelve million, one hundred twenty-two thousand, ninety-one".