21436343 has 2 divisors, whose sum is σ = 21436344. Its totient is φ = 21436342.

The previous prime is 21436339. The next prime is 21436361. The reversal of 21436343 is 34363412.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21436343 - 2² = 21436339 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21436333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10718171 + 10718172.

It is an arithmetic number, because the mean of its divisors is an integer number (10718172).

Almost surely, 2^21436343 is an apocalyptic number.

21436343 is a deficient number, since it is larger than the sum of its proper divisors (1).

21436343 is an equidigital number, since it uses as much as digits as its factorization.

21436343 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 21436343 is about 4629.9398484214. The cubic root of 21436343 is about 277.7901863909.

Adding to 21436343 its reverse (34363412), we get a palindrome (55799755).

The spelling of 21436343 in words is "twenty-one million, four hundred thirty-six thousand, three hundred forty-three".