21434559 has 4 divisors (see below), whose sum is σ = 28579416. Its totient is φ = 14289704.

The previous prime is 21434531. The next prime is 21434579. The reversal of 21434559 is 95543412.

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 21434559 - 2⁹ = 21434047 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21434579) 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, 3572424 + ... + 3572429.

It is an arithmetic number, because the mean of its divisors is an integer number (7144854).

Almost surely, 2^21434559 is an apocalyptic number.

21434559 is a deficient number, since it is larger than the sum of its proper divisors (7144857).

21434559 is an equidigital number, since it uses as much as digits as its factorization.

21434559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7144856.

The product of its digits is 21600, while the sum is 33.

The square root of 21434559 is about 4629.7471853223. The cubic root of 21434559 is about 277.7824799856.

The spelling of 21434559 in words is "twenty-one million, four hundred thirty-four thousand, five hundred fifty-nine".