22109891 has 2 divisors, whose sum is σ = 22109892. Its totient is φ = 22109890.

The previous prime is 22109827. The next prime is 22109903. The reversal of 22109891 is 19890122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 22109891 - 2⁶ = 22109827 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (22109821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11054945 + 11054946.

It is an arithmetic number, because the mean of its divisors is an integer number (11054946).

Almost surely, 2^22109891 is an apocalyptic number.

22109891 is a deficient number, since it is larger than the sum of its proper divisors (1).

22109891 is an equidigital number, since it uses as much as digits as its factorization.

22109891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 22109891 is about 4702.1155876903. The cubic root of 22109891 is about 280.6697022056.

The spelling of 22109891 in words is "twenty-two million, one hundred nine thousand, eight hundred ninety-one".