21223333 has 2 divisors, whose sum is σ = 21223334. Its totient is φ = 21223332.

The previous prime is 21223297. The next prime is 21223357. The reversal of 21223333 is 33332212.

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., 12830724 + 8392609 = 3582^2 + 2897^2 .

It is a cyclic number.

It is not a de Polignac number, because 21223333 - 2¹³ = 21215141 is a prime.

21223333 is a modest number, since divided by 3333 gives 2122 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 21223333.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21223393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611666 + 10611667.

It is an arithmetic number, because the mean of its divisors is an integer number (10611667).

Almost surely, 2^21223333 is an apocalyptic number.

It is an amenable number.

21223333 is a deficient number, since it is larger than the sum of its proper divisors (1).

21223333 is an equidigital number, since it uses as much as digits as its factorization.

21223333 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 19.

The square root of 21223333 is about 4606.8788783731. The cubic root of 21223333 is about 276.8670007557.

Adding to 21223333 its reverse (33332212), we get a palindrome (54555545).

The spelling of 21223333 in words is "twenty-one million, two hundred twenty-three thousand, three hundred thirty-three".