11993809 has 6 divisors (see below), whose sum is σ = 12328134. Its totient is φ = 11668320.

The previous prime is 11993801. The next prime is 11993843. The reversal of 11993809 is 90839911.

It can be written as a sum of positive squares in 3 ways, for example, as 3814209 + 8179600 = 1953^2 + 2860^2 .

It is not a de Polignac number, because 11993809 - 2³ = 11993801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11993801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3012 + ... + 5749.

It is an arithmetic number, because the mean of its divisors is an integer number (2054689).

Almost surely, 2^11993809 is an apocalyptic number.

It is an amenable number.

11993809 is a deficient number, since it is larger than the sum of its proper divisors (334325).

11993809 is an frugal number, since it uses more digits than its factorization.

11993809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8835 (or 8798 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 40.

The square root of 11993809 is about 3463.2079059739. The cubic root of 11993809 is about 228.9034699274.

The spelling of 11993809 in words is "eleven million, nine hundred ninety-three thousand, eight hundred nine".