2009569 has 4 divisors (see below), whose sum is σ = 2013444. Its totient is φ = 2005696.

The previous prime is 2009543. The next prime is 2009593. The reversal of 2009569 is 9659002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9659002 = 2 ⋅4829501.

It can be written as a sum of positive squares in 2 ways, for example, as 788544 + 1221025 = 888^2 + 1105^2 .

It is a cyclic number.

It is not a de Polignac number, because 2009569 - 2⁵ = 2009537 is a prime.

It is a super-2 number, since 2×2009569² = 8076735131522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

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 2009569.

It is not an unprimeable number, because it can be changed into a prime (2009509) 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, 1012 + ... + 2245.

It is an arithmetic number, because the mean of its divisors is an integer number (503361).

2^2009569 is an apocalyptic number.

It is an amenable number.

2009569 is a deficient number, since it is larger than the sum of its proper divisors (3875).

2009569 is an equidigital number, since it uses as much as digits as its factorization.

2009569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3874.

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 2009569 is about 1417.5926777463. The cubic root of 2009569 is about 126.1927217873.

It can be divided in two parts, 20095 and 69, that added together give a square (20164 = 142²).

The spelling of 2009569 in words is "two million, nine thousand, five hundred sixty-nine".