21124343 has 2 divisors, whose sum is σ = 21124344. Its totient is φ = 21124342.

The previous prime is 21124339. The next prime is 21124349. The reversal of 21124343 is 34342112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21124343 - 2² = 21124339 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21124349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10562171 + 10562172.

It is an arithmetic number, because the mean of its divisors is an integer number (10562172).

Almost surely, 2^21124343 is an apocalyptic number.

21124343 is a deficient number, since it is larger than the sum of its proper divisors (1).

21124343 is an equidigital number, since it uses as much as digits as its factorization.

21124343 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 576, while the sum is 20.

The square root of 21124343 is about 4596.1226049791. The cubic root of 21124343 is about 276.4358748514.

Adding to 21124343 its reverse (34342112), we get a palindrome (55466455).

The spelling of 21124343 in words is "twenty-one million, one hundred twenty-four thousand, three hundred forty-three".