21716043 has 8 divisors (see below), whose sum is σ = 29062656. Its totient is φ = 14423400.

The previous prime is 21716033. The next prime is 21716047. The reversal of 21716043 is 34061712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21716043 - 2¹⁸ = 21453899 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21716047) 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 in 7 ways as a sum of consecutive naturals, for example, 12543 + ... + 14168.

It is an arithmetic number, because the mean of its divisors is an integer number (3632832).

Almost surely, 2^21716043 is an apocalyptic number.

21716043 is a deficient number, since it is larger than the sum of its proper divisors (7346613).

21716043 is a wasteful number, since it uses less digits than its factorization.

21716043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26985.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 21716043 is about 4660.0475319464. The cubic root of 21716043 is about 278.9931653880.

Adding to 21716043 its reverse (34061712), we get a palindrome (55777755).

The spelling of 21716043 in words is "twenty-one million, seven hundred sixteen thousand, forty-three".