21255313983209 has 8 divisors (see below), whose sum is σ = 21707680195200. Its totient is φ = 20802953000016.

The previous prime is 21255313983203. The next prime is 21255313983227. The reversal of 21255313983209 is 90238931355212.

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 21255313983209 - 2¹² = 21255313979113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21255313983203) 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, 7539842 + ... + 9967940.

It is an arithmetic number, because the mean of its divisors is an integer number (2713460024400).

Almost surely, 2^{21255313983209} is an apocalyptic number.

It is an amenable number.

21255313983209 is a deficient number, since it is larger than the sum of its proper divisors (452366211991).

21255313983209 is a wasteful number, since it uses less digits than its factorization.

21255313983209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2614399.

The product of its (nonzero) digits is 3499200, while the sum is 53.

The spelling of 21255313983209 in words is "twenty-one trillion, two hundred fifty-five billion, three hundred thirteen million, nine hundred eighty-three thousand, two hundred nine".