11821287 has 32 divisors (see below), whose sum is σ = 17694720. Its totient is φ = 6985440.

The previous prime is 11821283. The next prime is 11821289. The reversal of 11821287 is 78212811.

It is a happy number.

11821287 is digitally balanced in base 2, base 3 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11821287 - 2² = 11821283 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11821283) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 93018 + ... + 93144.

It is an arithmetic number, because the mean of its divisors is an integer number (552960).

Almost surely, 2^11821287 is an apocalyptic number.

11821287 is a deficient number, since it is larger than the sum of its proper divisors (5873433).

11821287 is a wasteful number, since it uses less digits than its factorization.

11821287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243.

The product of its digits is 1792, while the sum is 30.

The square root of 11821287 is about 3438.2098539792. The cubic root of 11821287 is about 227.8006298090.

The spelling of 11821287 in words is "eleven million, eight hundred twenty-one thousand, two hundred eighty-seven".