2209689 has 6 divisors (see below), whose sum is σ = 3191786. Its totient is φ = 1473120.

The previous prime is 2209687. The next prime is 2209693. The reversal of 2209689 is 9869022.

2209689 = T₃₉₁ + T₃₉₂ + ... + T₄₁₇.

It can be written as a sum of positive squares in only one way, i.e., 2152089 + 57600 = 1467^2 + 240^2 .

It is not a de Polignac number, because 2209689 - 2¹ = 2209687 is a prime.

It is a Duffinian number.

It is a Curzon 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 5 ways as a sum of consecutive naturals, for example, 122752 + ... + 122769.

2^2209689 is an apocalyptic number.

It is an amenable number.

2209689 is a deficient number, since it is larger than the sum of its proper divisors (982097).

2209689 is a wasteful number, since it uses less digits than its factorization.

2209689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245527 (or 245524 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 2209689 is about 1486.5022704322. The cubic root of 2209689 is about 130.2497958424.

The spelling of 2209689 in words is "two million, two hundred nine thousand, six hundred eighty-nine".