20442021191 has 2 divisors, whose sum is σ = 20442021192. Its totient is φ = 20442021190.

The previous prime is 20442021143. The next prime is 20442021217. The reversal of 20442021191 is 19112024402.

It is an a-pointer prime, because the next prime (20442021217) can be obtained adding 20442021191 to its sum of digits (26).

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20442021191 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20442021191.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20442024191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10221010595 + 10221010596.

It is an arithmetic number, because the mean of its divisors is an integer number (10221010596).

Almost surely, 2^20442021191 is an apocalyptic number.

20442021191 is a deficient number, since it is larger than the sum of its proper divisors (1).

20442021191 is an equidigital number, since it uses as much as digits as its factorization.

20442021191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 26.

Adding to 20442021191 its reverse (19112024402), we get a palindrome (39554045593).

The spelling of 20442021191 in words is "twenty billion, four hundred forty-two million, twenty-one thousand, one hundred ninety-one".