21682533 has 16 divisors (see below), whose sum is σ = 29521856. Its totient is φ = 14152320.

The previous prime is 21682519. The next prime is 21682589. The reversal of 21682533 is 33528612.

It is not a de Polignac number, because 21682533 - 2⁵ = 21682501 is a prime.

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 21682533.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21682433) 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 15 ways as a sum of consecutive naturals, for example, 39366 + ... + 39912.

It is an arithmetic number, because the mean of its divisors is an integer number (1845116).

Almost surely, 2^21682533 is an apocalyptic number.

It is an amenable number.

21682533 is a deficient number, since it is larger than the sum of its proper divisors (7839323).

21682533 is a wasteful number, since it uses less digits than its factorization.

21682533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 804.

The product of its digits is 8640, while the sum is 30.

The square root of 21682533 is about 4656.4506869503. The cubic root of 21682533 is about 278.8495868373.

The spelling of 21682533 in words is "twenty-one million, six hundred eighty-two thousand, five hundred thirty-three".