817221444 has 48 divisors (see below), whose sum is σ = 2064246912. Its totient is φ = 250140672.

The previous prime is 817221443. The next prime is 817221491. The reversal of 817221444 is 444122718.

817221444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (817221443) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16537 + ... + 43679.

It is an arithmetic number, because the mean of its divisors is an integer number (43005144).

Almost surely, 2^817221444 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 817221444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1032123456).

817221444 is an abundant number, since it is smaller than the sum of its proper divisors (1247025468).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

817221444 is a wasteful number, since it uses less digits than its factorization.

817221444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27356 (or 27354 counting only the distinct ones).

The product of its digits is 14336, while the sum is 33.

The square root of 817221444 is about 28587.0852659029. The cubic root of 817221444 is about 934.9317704032.

The spelling of 817221444 in words is "eight hundred seventeen million, two hundred twenty-one thousand, four hundred forty-four".