21734543 has 4 divisors (see below), whose sum is σ = 22484040. Its totient is φ = 20985048.

The previous prime is 21734527. The next prime is 21734593. The reversal of 21734543 is 34543712.

It is a happy number.

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 21734543 - 2⁴ = 21734527 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 749467 = 21734543 / (2 + 1 + 7 + 3 + 4 + 5 + 4 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21734593) 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 3 ways as a sum of consecutive naturals, for example, 374705 + ... + 374762.

It is an arithmetic number, because the mean of its divisors is an integer number (5621010).

Almost surely, 2^21734543 is an apocalyptic number.

21734543 is a deficient number, since it is larger than the sum of its proper divisors (749497).

21734543 is an equidigital number, since it uses as much as digits as its factorization.

21734543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 749496.

The product of its digits is 10080, while the sum is 29.

The square root of 21734543 is about 4662.0320676718. The cubic root of 21734543 is about 279.0723681014.

The spelling of 21734543 in words is "twenty-one million, seven hundred thirty-four thousand, five hundred forty-three".