11811439 has 4 divisors (see below), whose sum is σ = 12218760. Its totient is φ = 11404120.

The previous prime is 11811433. The next prime is 11811451. The reversal of 11811439 is 93411811.

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 11811439 - 2³ = 11811431 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11811431) 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, 203617 + ... + 203674.

It is an arithmetic number, because the mean of its divisors is an integer number (3054690).

Almost surely, 2^11811439 is an apocalyptic number.

11811439 is a deficient number, since it is larger than the sum of its proper divisors (407321).

11811439 is an equidigital number, since it uses as much as digits as its factorization.

11811439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407320.

The product of its digits is 864, while the sum is 28.

The square root of 11811439 is about 3436.7774149630. Note that the first 3 decimals coincide. The cubic root of 11811439 is about 227.7373540179.

The spelling of 11811439 in words is "eleven million, eight hundred eleven thousand, four hundred thirty-nine".