221500609 has 4 divisors (see below), whose sum is σ = 241637040. Its totient is φ = 201364180.

The previous prime is 221500597. The next prime is 221500639. The reversal of 221500609 is 906005122.

221500609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 221500609 - 2⁷ = 221500481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221500639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10068199 + ... + 10068220.

It is an arithmetic number, because the mean of its divisors is an integer number (60409260).

Almost surely, 2^221500609 is an apocalyptic number.

It is an amenable number.

221500609 is a deficient number, since it is larger than the sum of its proper divisors (20136431).

221500609 is a wasteful number, since it uses less digits than its factorization.

221500609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20136430.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 221500609 is about 14882.8965258783. The cubic root of 221500609 is about 605.0505242053.

The spelling of 221500609 in words is "two hundred twenty-one million, five hundred thousand, six hundred nine".