21221333333 has 2 divisors, whose sum is σ = 21221333334. Its totient is φ = 21221333332.

The previous prime is 21221333317. The next prime is 21221333347. The reversal of 21221333333 is 33333312212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18219060484 + 3002272849 = 134978^2 + 54793^2 .

It is a cyclic number.

It is not a de Polignac number, because 21221333333 - 2⁴ = 21221333317 is a prime.

21221333333 is a modest number, since divided by 333333 gives 21221 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21221333303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610666666 + 10610666667.

It is an arithmetic number, because the mean of its divisors is an integer number (10610666667).

Almost surely, 2^21221333333 is an apocalyptic number.

It is an amenable number.

21221333333 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221333333 is an equidigital number, since it uses as much as digits as its factorization.

21221333333 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5832, while the sum is 26.

Adding to 21221333333 its reverse (33333312212), we get a palindrome (54554645545).

The spelling of 21221333333 in words is "twenty-one billion, two hundred twenty-one million, three hundred thirty-three thousand, three hundred thirty-three".