5561209 has 2 divisors, whose sum is σ = 5561210. Its totient is φ = 5561208.

The previous prime is 5561207. The next prime is 5561219. The reversal of 5561209 is 9021655.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3250809 + 2310400 = 1803^2 + 1520^2 .

It is a cyclic number.

It is not a de Polignac number, because 5561209 - 2¹ = 5561207 is a prime.

Together with 5561207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (5561207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2780604 + 2780605.

It is an arithmetic number, because the mean of its divisors is an integer number (2780605).

Almost surely, 2^5561209 is an apocalyptic number.

It is an amenable number.

5561209 is a deficient number, since it is larger than the sum of its proper divisors (1).

5561209 is an equidigital number, since it uses as much as digits as its factorization.

5561209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2700, while the sum is 28.

The square root of 5561209 is about 2358.2215756794. The cubic root of 5561209 is about 177.1698179753.

The spelling of 5561209 in words is "five million, five hundred sixty-one thousand, two hundred nine".