21244343 has 4 divisors (see below), whose sum is σ = 21397320. Its totient is φ = 21091368.

The previous prime is 21244309. The next prime is 21244367. The reversal of 21244343 is 34344212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21244343 - 2²² = 17050039 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21244303) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 76280 + ... + 76557.

It is an arithmetic number, because the mean of its divisors is an integer number (5349330).

Almost surely, 2^21244343 is an apocalyptic number.

21244343 is a deficient number, since it is larger than the sum of its proper divisors (152977).

21244343 is a wasteful number, since it uses less digits than its factorization.

21244343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152976.

The product of its digits is 2304, while the sum is 23.

The square root of 21244343 is about 4609.1586000050. The cubic root of 21244343 is about 276.9583319530.

Adding to 21244343 its reverse (34344212), we get a palindrome (55588555).

The spelling of 21244343 in words is "twenty-one million, two hundred forty-four thousand, three hundred forty-three".