11809939 has 4 divisors (see below), whose sum is σ = 11828520. Its totient is φ = 11791360.

The previous prime is 11809933. The next prime is 11809943. The reversal of 11809939 is 93990811.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11809939 - 2¹¹ = 11807891 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11809933) 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 3 ways as a sum of consecutive naturals, for example, 8302 + ... + 9619.

It is an arithmetic number, because the mean of its divisors is an integer number (2957130).

Almost surely, 2^11809939 is an apocalyptic number.

11809939 is a deficient number, since it is larger than the sum of its proper divisors (18581).

11809939 is an equidigital number, since it uses as much as digits as its factorization.

11809939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18580.

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

The square root of 11809939 is about 3436.5591803430. The cubic root of 11809939 is about 227.7277130675.

The spelling of 11809939 in words is "eleven million, eight hundred nine thousand, nine hundred thirty-nine".