221530809 has 8 divisors (see below), whose sum is σ = 295500160. Its totient is φ = 147624336.

The previous prime is 221530801. The next prime is 221530919. The reversal of 221530809 is 908035122.

It is a happy number.

221530809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 221530809 - 2³ = 221530801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221530801) 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, 6769 + ... + 22110.

It is an arithmetic number, because the mean of its divisors is an integer number (36937520).

Almost surely, 2^221530809 is an apocalyptic number.

It is an amenable number.

221530809 is a deficient number, since it is larger than the sum of its proper divisors (73969351).

221530809 is a wasteful number, since it uses less digits than its factorization.

221530809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31439.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 221530809 is about 14883.9110787454. The cubic root of 221530809 is about 605.0780210378.

The spelling of 221530809 in words is "two hundred twenty-one million, five hundred thirty thousand, eight hundred nine".