21659981833 has 8 divisors (see below), whose sum is σ = 24769739520. Its totient is φ = 18554092800.

The previous prime is 21659981813. The next prime is 21659981867. The reversal of 21659981833 is 33818995612.

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 21659981833 - 2²⁵ = 21626427401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21659981803) 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, 955153 + ... + 977566.

It is an arithmetic number, because the mean of its divisors is an integer number (3096217440).

Almost surely, 2^21659981833 is an apocalyptic number.

It is an amenable number.

21659981833 is a deficient number, since it is larger than the sum of its proper divisors (3109757687).

21659981833 is a wasteful number, since it uses less digits than its factorization.

21659981833 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1934327.

The product of its digits is 2799360, while the sum is 55.

The spelling of 21659981833 in words is "twenty-one billion, six hundred fifty-nine million, nine hundred eighty-one thousand, eight hundred thirty-three".