21211433 has 2 divisors, whose sum is σ = 21211434. Its totient is φ = 21211432.

The previous prime is 21211403. The next prime is 21211481. The reversal of 21211433 is 33411212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15272464 + 5938969 = 3908^2 + 2437^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211433 - 2⁶ = 21211369 is a prime.

It is not a weakly prime, because it can be changed into another prime (21211403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605716 + 10605717.

It is an arithmetic number, because the mean of its divisors is an integer number (10605717).

Almost surely, 2^21211433 is an apocalyptic number.

It is an amenable number.

21211433 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211433 is an equidigital number, since it uses as much as digits as its factorization.

21211433 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 144, while the sum is 17.

The square root of 21211433 is about 4605.5871504076. The cubic root of 21211433 is about 276.8152443031.

Adding to 21211433 its reverse (33411212), we get a palindrome (54622645).

The spelling of 21211433 in words is "twenty-one million, two hundred eleven thousand, four hundred thirty-three".