1123821 has 16 divisors (see below), whose sum is σ = 1684800. Its totient is φ = 740304.

The previous prime is 1123807. The next prime is 1123841. The reversal of 1123821 is 1283211.

It is not a de Polignac number, because 1123821 - 2⁷ = 1123693 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1123794 and 1123803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1123841) 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 15 ways as a sum of consecutive naturals, for example, 2695 + ... + 3083.

It is an arithmetic number, because the mean of its divisors is an integer number (105300).

2^1123821 is an apocalyptic number.

It is an amenable number.

1123821 is a deficient number, since it is larger than the sum of its proper divisors (560979).

1123821 is a wasteful number, since it uses less digits than its factorization.

1123821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505 (or 499 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

The square root of 1123821 is about 1060.1042401575. The cubic root of 1123821 is about 103.9678463224.

It can be divided in two parts, 11 and 23821, that added together give a palindrome (23832).

The spelling of 1123821 in words is "one million, one hundred twenty-three thousand, eight hundred twenty-one".