21364433 has 2 divisors, whose sum is σ = 21364434. Its totient is φ = 21364432.

The previous prime is 21364423. The next prime is 21364451. The reversal of 21364433 is 33446312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20857489 + 506944 = 4567^2 + 712^2 .

It is a cyclic number.

It is not a de Polignac number, because 21364433 - 2¹⁰ = 21363409 is a prime.

It is a super-2 number, since 2×21364433² = 912877994822978, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21364423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10682216 + 10682217.

It is an arithmetic number, because the mean of its divisors is an integer number (10682217).

Almost surely, 2^21364433 is an apocalyptic number.

It is an amenable number.

21364433 is a deficient number, since it is larger than the sum of its proper divisors (1).

21364433 is an equidigital number, since it uses as much as digits as its factorization.

21364433 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 26.

The square root of 21364433 is about 4622.1675651149. The cubic root of 21364433 is about 277.4792149570.

It can be divided in two parts, 213 and 64433, that added together give a palindrome (64646).

The spelling of 21364433 in words is "twenty-one million, three hundred sixty-four thousand, four hundred thirty-three".