21221242033 has 2 divisors, whose sum is σ = 21221242034. Its totient is φ = 21221242032.

The previous prime is 21221242019. The next prime is 21221242039. The reversal of 21221242033 is 33024212212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14558111649 + 6663130384 = 120657^2 + 81628^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21221242033 is a prime.

It is a super-2 number, since 2×21221242033² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21221241995 and 21221242013.

It is not a weakly prime, because it can be changed into another prime (21221242039) 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, 10610621016 + 10610621017.

It is an arithmetic number, because the mean of its divisors is an integer number (10610621017).

Almost surely, 2^21221242033 is an apocalyptic number.

It is an amenable number.

21221242033 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221242033 is an equidigital number, since it uses as much as digits as its factorization.

21221242033 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 22.

Adding to 21221242033 its reverse (33024212212), we get a palindrome (54245454245).

The spelling of 21221242033 in words is "twenty-one billion, two hundred twenty-one million, two hundred forty-two thousand, thirty-three".