21220575833 has 2 divisors, whose sum is σ = 21220575834. Its totient is φ = 21220575832.

The previous prime is 21220575791. The next prime is 21220575841. The reversal of 21220575833 is 33857502212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12035845264 + 9184730569 = 109708^2 + 95837^2 .

It is a cyclic number.

It is not a de Polignac number, because 21220575833 - 2⁶ = 21220575769 is a prime.

It is not a weakly prime, because it can be changed into another prime (21220575863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610287916 + 10610287917.

It is an arithmetic number, because the mean of its divisors is an integer number (10610287917).

Almost surely, 2^21220575833 is an apocalyptic number.

It is an amenable number.

21220575833 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220575833 is an equidigital number, since it uses as much as digits as its factorization.

21220575833 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 100800, while the sum is 38.

The spelling of 21220575833 in words is "twenty-one billion, two hundred twenty million, five hundred seventy-five thousand, eight hundred thirty-three".