21444767209 has 8 divisors (see below), whose sum is σ = 22414396032. Its totient is φ = 20478242400.

The previous prime is 21444767177. The next prime is 21444767243. The reversal of 21444767209 is 90276744412.

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 21444767209 - 2⁵ = 21444767177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21444767809) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 761869 + ... + 789514.

It is an arithmetic number, because the mean of its divisors is an integer number (2801799504).

Almost surely, 2^21444767209 is an apocalyptic number.

It is an amenable number.

21444767209 is a deficient number, since it is larger than the sum of its proper divisors (969628823).

21444767209 is a wasteful number, since it uses less digits than its factorization.

21444767209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1552007.

The product of its (nonzero) digits is 677376, while the sum is 46.

The spelling of 21444767209 in words is "twenty-one billion, four hundred forty-four million, seven hundred sixty-seven thousand, two hundred nine".