11821865 has 8 divisors (see below), whose sum is σ = 15475968. Its totient is φ = 8597680.

The previous prime is 11821853. The next prime is 11821871. The reversal of 11821865 is 56812811.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 11821865 - 2¹⁰ = 11820841 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 107417 + ... + 107526.

It is an arithmetic number, because the mean of its divisors is an integer number (1934496).

Almost surely, 2^11821865 is an apocalyptic number.

It is an amenable number.

11821865 is a deficient number, since it is larger than the sum of its proper divisors (3654103).

11821865 is a wasteful number, since it uses less digits than its factorization.

11821865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214959.

The product of its digits is 3840, while the sum is 32.

The square root of 11821865 is about 3438.2939083214. The cubic root of 11821865 is about 227.8043425073.

The spelling of 11821865 in words is "eleven million, eight hundred twenty-one thousand, eight hundred sixty-five".