1821231 has 8 divisors (see below), whose sum is σ = 2698160. Its totient is φ = 1214136.

The previous prime is 1821191. The next prime is 1821233. The reversal of 1821231 is 1321281.

It is not a de Polignac number, because 1821231 - 2⁶ = 1821167 is a prime.

It is a super-2 number, since 2×1821231² = 6633764710722, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1821233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33700 + ... + 33753.

It is an arithmetic number, because the mean of its divisors is an integer number (337270).

2^1821231 is an apocalyptic number.

1821231 is a deficient number, since it is larger than the sum of its proper divisors (876929).

1821231 is an equidigital number, since it uses as much as digits as its factorization.

1821231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67462 (or 67456 counting only the distinct ones).

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

The square root of 1821231 is about 1349.5299181567. The cubic root of 1821231 is about 122.1204355801.

The spelling of 1821231 in words is "one million, eight hundred twenty-one thousand, two hundred thirty-one".