21221122122191 has 2 divisors, whose sum is σ = 21221122122192. Its totient is φ = 21221122122190.

The previous prime is 21221122122107. The next prime is 21221122122281. The reversal of 21221122122191 is 19122122112212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21221122122191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21221122122391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610561061095 + 10610561061096.

It is an arithmetic number, because the mean of its divisors is an integer number (10610561061096).

Almost surely, 2^{21221122122191} is an apocalyptic number.

21221122122191 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221122122191 is an equidigital number, since it uses as much as digits as its factorization.

21221122122191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 29.

The spelling of 21221122122191 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twenty-two million, one hundred twenty-two thousand, one hundred ninety-one".