2221609 has 8 divisors (see below), whose sum is σ = 2426312. Its totient is φ = 2021760.

The previous prime is 2221589. The next prime is 2221631. The reversal of 2221609 is 9061222.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 205209 + 2016400 = 453^2 + 1420^2 .

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

It is not a de Polignac number, because 2221609 - 2⁹ = 2221097 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2221609.

It is not an unprimeable number, because it can be changed into a prime (2221669) 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, 222 + ... + 2119.

It is an arithmetic number, because the mean of its divisors is an integer number (303289).

2^2221609 is an apocalyptic number.

It is an amenable number.

2221609 is a deficient number, since it is larger than the sum of its proper divisors (204703).

2221609 is a wasteful number, since it uses less digits than its factorization.

2221609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2427.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 2221609 is about 1490.5062898224. The cubic root of 2221609 is about 130.4835835155.

The spelling of 2221609 in words is "two million, two hundred twenty-one thousand, six hundred nine".