21889843 has 8 divisors (see below), whose sum is σ = 23101520. Its totient is φ = 20684160.

The previous prime is 21889841. The next prime is 21889871. The reversal of 21889843 is 34898812.

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

It is not a de Polignac number, because 21889843 - 2¹ = 21889841 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 21889843.

It is not an unprimeable number, because it can be changed into a prime (21889841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7423 + ... + 9943.

It is an arithmetic number, because the mean of its divisors is an integer number (2887690).

Almost surely, 2^21889843 is an apocalyptic number.

21889843 is a deficient number, since it is larger than the sum of its proper divisors (1211677).

21889843 is a wasteful number, since it uses less digits than its factorization.

21889843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2997.

The product of its digits is 110592, while the sum is 43.

The square root of 21889843 is about 4678.6582478313. The cubic root of 21889843 is about 279.7354772184.

The spelling of 21889843 in words is "twenty-one million, eight hundred eighty-nine thousand, eight hundred forty-three".