21442533 has 8 divisors (see below), whose sum is σ = 32674368. Its totient is φ = 12252864.

The previous prime is 21442501. The next prime is 21442543. The reversal of 21442533 is 33524412.

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

It is not a de Polignac number, because 21442533 - 2⁵ = 21442501 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21442543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 510516 + ... + 510557.

It is an arithmetic number, because the mean of its divisors is an integer number (4084296).

Almost surely, 2^21442533 is an apocalyptic number.

It is an amenable number.

21442533 is a deficient number, since it is larger than the sum of its proper divisors (11231835).

21442533 is a wasteful number, since it uses less digits than its factorization.

21442533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1021083.

The product of its digits is 2880, while the sum is 24.

The square root of 21442533 is about 4630.6082753781. The cubic root of 21442533 is about 277.8169222287.

Adding to 21442533 its reverse (33524412), we get a palindrome (54966945).

The spelling of 21442533 in words is "twenty-one million, four hundred forty-two thousand, five hundred thirty-three".