11823921 has 8 divisors (see below), whose sum is σ = 17516960. Its totient is φ = 7882596.

The previous prime is 11823907. The next prime is 11823923. The reversal of 11823921 is 12932811.

11823921 is digitally balanced in base 2 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 11823921 - 2¹⁸ = 11561777 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 437923 = 11823921 / (1 + 1 + 8 + 2 + 3 + 9 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11823923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 218935 + ... + 218988.

It is an arithmetic number, because the mean of its divisors is an integer number (2189620).

Almost surely, 2^11823921 is an apocalyptic number.

It is an amenable number.

11823921 is a deficient number, since it is larger than the sum of its proper divisors (5693039).

11823921 is an equidigital number, since it uses as much as digits as its factorization.

11823921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437932 (or 437926 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 11823921 is about 3438.5928808162. The cubic root of 11823921 is about 227.8175479415.

The spelling of 11823921 in words is "eleven million, eight hundred twenty-three thousand, nine hundred twenty-one".