2209685 has 4 divisors (see below), whose sum is σ = 2651628. Its totient is φ = 1767744.

The previous prime is 2209667. The next prime is 2209687. The reversal of 2209685 is 5869022.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5869022 = 2 ⋅2934511.

It can be written as a sum of positive squares in 2 ways, for example, as 1331716 + 877969 = 1154^2 + 937^2 .

It is a cyclic number.

It is not a de Polignac number, because 2209685 - 2¹² = 2205589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2209687) 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, 220964 + ... + 220973.

It is an arithmetic number, because the mean of its divisors is an integer number (662907).

2^2209685 is an apocalyptic number.

It is an amenable number.

2209685 is a deficient number, since it is larger than the sum of its proper divisors (441943).

2209685 is an equidigital number, since it uses as much as digits as its factorization.

2209685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441942.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 2209685 is about 1486.5009249913. The cubic root of 2209685 is about 130.2497172492.

The spelling of 2209685 in words is "two million, two hundred nine thousand, six hundred eighty-five".