21433459 has 4 divisors (see below), whose sum is σ = 21455280. Its totient is φ = 21411640.

The previous prime is 21433453. The next prime is 21433469. The reversal of 21433459 is 95433412.

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 21433459 - 2⁵ = 21433427 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21433459.

It is not an unprimeable number, because it can be changed into a prime (21433453) 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, 9364 + ... + 11425.

It is an arithmetic number, because the mean of its divisors is an integer number (5363820).

Almost surely, 2^21433459 is an apocalyptic number.

21433459 is a deficient number, since it is larger than the sum of its proper divisors (21821).

21433459 is a wasteful number, since it uses less digits than its factorization.

21433459 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21820.

The product of its digits is 12960, while the sum is 31.

The square root of 21433459 is about 4629.6283868146. The cubic root of 21433459 is about 277.7777280652. Note that the first 4 decimals are identical.

The spelling of 21433459 in words is "twenty-one million, four hundred thirty-three thousand, four hundred fifty-nine".