11775821 has 4 divisors (see below), whose sum is σ = 11868672. Its totient is φ = 11682972.

The previous prime is 11775817. The next prime is 11775823. The reversal of 11775821 is 12857711.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11775821 - 2² = 11775817 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 (11775823) 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, 46235 + ... + 46488.

It is an arithmetic number, because the mean of its divisors is an integer number (2967168).

Almost surely, 2^11775821 is an apocalyptic number.

It is an amenable number.

11775821 is a deficient number, since it is larger than the sum of its proper divisors (92851).

11775821 is an equidigital number, since it uses as much as digits as its factorization.

11775821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92850.

The product of its digits is 3920, while the sum is 32.

The square root of 11775821 is about 3431.5916132314. The cubic root of 11775821 is about 227.5082056373.

The spelling of 11775821 in words is "eleven million, seven hundred seventy-five thousand, eight hundred twenty-one".