18221759 has 8 divisors (see below), whose sum is σ = 18701760. Its totient is φ = 17745696.

The previous prime is 18221743. The next prime is 18221761. The reversal of 18221759 is 95712281.

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

It is not a de Polignac number, because 18221759 - 2⁴ = 18221743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18221729) 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, 9917 + ... + 11609.

It is an arithmetic number, because the mean of its divisors is an integer number (2337720).

Almost surely, 2^18221759 is an apocalyptic number.

18221759 is a deficient number, since it is larger than the sum of its proper divisors (480001).

18221759 is a wasteful number, since it uses less digits than its factorization.

18221759 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1969.

The product of its digits is 10080, while the sum is 35.

The square root of 18221759 is about 4268.6952339093. The cubic root of 18221759 is about 263.1459959399.

The spelling of 18221759 in words is "eighteen million, two hundred twenty-one thousand, seven hundred fifty-nine".