21223330091 has 2 divisors, whose sum is σ = 21223330092. Its totient is φ = 21223330090.

The previous prime is 21223330061. The next prime is 21223330151. The reversal of 21223330091 is 19003332212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21223330091 - 2¹⁰ = 21223329067 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21223330091.

It is not a weakly prime, because it can be changed into another prime (21223330031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611665045 + 10611665046.

It is an arithmetic number, because the mean of its divisors is an integer number (10611665046).

Almost surely, 2^21223330091 is an apocalyptic number.

21223330091 is a deficient number, since it is larger than the sum of its proper divisors (1).

21223330091 is an equidigital number, since it uses as much as digits as its factorization.

21223330091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 26.

The spelling of 21223330091 in words is "twenty-one billion, two hundred twenty-three million, three hundred thirty thousand, ninety-one".