21845933 has 4 divisors (see below), whose sum is σ = 21992700. Its totient is φ = 21699168.

The previous prime is 21845909. The next prime is 21845959. The reversal of 21845933 is 33954812.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6620329 + 15225604 = 2573^2 + 3902^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21845933 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21845893 and 21845902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21845963) 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, 73160 + ... + 73457.

It is an arithmetic number, because the mean of its divisors is an integer number (5498175).

Almost surely, 2^21845933 is an apocalyptic number.

It is an amenable number.

21845933 is a deficient number, since it is larger than the sum of its proper divisors (146767).

21845933 is a wasteful number, since it uses less digits than its factorization.

21845933 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146766.

The product of its digits is 25920, while the sum is 35.

The square root of 21845933 is about 4673.9633075154. The cubic root of 21845933 is about 279.5483065881.

The spelling of 21845933 in words is "twenty-one million, eight hundred forty-five thousand, nine hundred thirty-three".