21343073 has 4 divisors (see below), whose sum is σ = 21704880. Its totient is φ = 20981268.

The previous prime is 21343039. The next prime is 21343111. The reversal of 21343073 is 37034312.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21343073 - 2⁶ = 21343009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21343013) 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, 180815 + ... + 180932.

It is an arithmetic number, because the mean of its divisors is an integer number (5426220).

Almost surely, 2^21343073 is an apocalyptic number.

It is an amenable number.

21343073 is a deficient number, since it is larger than the sum of its proper divisors (361807).

21343073 is an equidigital number, since it uses as much as digits as its factorization.

21343073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361806.

The product of its (nonzero) digits is 1512, while the sum is 23.

The square root of 21343073 is about 4619.8563830492. The cubic root of 21343073 is about 277.3867102418.

Adding to 21343073 its reverse (37034312), we get a palindrome (58377385).

The spelling of 21343073 in words is "twenty-one million, three hundred forty-three thousand, seventy-three".