21442833 has 8 divisors (see below), whose sum is σ = 31767200. Its totient is φ = 14295204.

The previous prime is 21442819. The next prime is 21442871. The reversal of 21442833 is 33824412.

It is not a de Polignac number, because 21442833 - 2²¹ = 19345681 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 794179 = 21442833 / (2 + 1 + 4 + 4 + 2 + 8 + 3 + 3).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21442797 and 21442806.

It is not an unprimeable number, because it can be changed into a prime (21442133) 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, 397063 + ... + 397116.

It is an arithmetic number, because the mean of its divisors is an integer number (3970900).

Almost surely, 2^21442833 is an apocalyptic number.

It is an amenable number.

21442833 is a deficient number, since it is larger than the sum of its proper divisors (10324367).

21442833 is an equidigital number, since it uses as much as digits as its factorization.

21442833 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 794188 (or 794182 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

The square root of 21442833 is about 4630.6406684173. The cubic root of 21442833 is about 277.8182178575.

The spelling of 21442833 in words is "twenty-one million, four hundred forty-two thousand, eight hundred thirty-three".