21859673 has 8 divisors (see below), whose sum is σ = 23938176. Its totient is φ = 19796400.

The previous prime is 21859661. The next prime is 21859679. The reversal of 21859673 is 37695812.

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

It is a cyclic number.

It is not a de Polignac number, because 21859673 - 2¹⁰ = 21858649 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 21859673.

It is not an unprimeable number, because it can be changed into a prime (21859679) 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 7 ways as a sum of consecutive naturals, for example, 686 + ... + 6647.

It is an arithmetic number, because the mean of its divisors is an integer number (2992272).

Almost surely, 2^21859673 is an apocalyptic number.

It is an amenable number.

21859673 is a deficient number, since it is larger than the sum of its proper divisors (2078503).

21859673 is a wasteful number, since it uses less digits than its factorization.

21859673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7615.

The product of its digits is 90720, while the sum is 41.

The square root of 21859673 is about 4675.4329211315. The cubic root of 21859673 is about 279.6069016098.

The spelling of 21859673 in words is "twenty-one million, eight hundred fifty-nine thousand, six hundred seventy-three".