11821861 has 8 divisors (see below), whose sum is σ = 12297824. Its totient is φ = 11355120.

The previous prime is 11821853. The next prime is 11821871. The reversal of 11821861 is 16812811.

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

It is a cyclic number.

It is not a de Polignac number, because 11821861 - 2³ = 11821853 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 (11821841) 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 7 ways as a sum of consecutive naturals, for example, 370 + ... + 4876.

It is an arithmetic number, because the mean of its divisors is an integer number (1537228).

Almost surely, 2^11821861 is an apocalyptic number.

It is an amenable number.

11821861 is a deficient number, since it is larger than the sum of its proper divisors (475963).

11821861 is an equidigital number, since it uses as much as digits as its factorization.

11821861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4611.

The product of its digits is 768, while the sum is 28.

The square root of 11821861 is about 3438.2933266375. The cubic root of 11821861 is about 227.8043168143.

The spelling of 11821861 in words is "eleven million, eight hundred twenty-one thousand, eight hundred sixty-one".