11042809 has 4 divisors (see below), whose sum is σ = 11692404. Its totient is φ = 10393216.

The previous prime is 11042807. The next prime is 11042813. The reversal of 11042809 is 90824011.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90824011 = 37 ⋅2454703.

It can be written as a sum of positive squares in 2 ways, for example, as 4717584 + 6325225 = 2172^2 + 2515^2 .

It is a cyclic number.

It is not a de Polignac number, because 11042809 - 2¹ = 11042807 is a prime.

It is a super-2 number, since 2×11042809² = 243887261220962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11042803) 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, 324772 + ... + 324805.

It is an arithmetic number, because the mean of its divisors is an integer number (2923101).

Almost surely, 2^11042809 is an apocalyptic number.

It is an amenable number.

11042809 is a deficient number, since it is larger than the sum of its proper divisors (649595).

11042809 is an equidigital number, since it uses as much as digits as its factorization.

11042809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649594.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 11042809 is about 3323.0722231092. The cubic root of 11042809 is about 222.6861397366.

The spelling of 11042809 in words is "eleven million, forty-two thousand, eight hundred nine".