1321831 has 4 divisors (see below), whose sum is σ = 1510672. Its totient is φ = 1132992.

The previous prime is 1321823. The next prime is 1321841. The reversal of 1321831 is 1381231.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1321831 - 2³ = 1321823 is a prime.

It is a super-2 number, since 2×1321831² = 3494474385122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1321799 and 1321808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321841) 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 3 ways as a sum of consecutive naturals, for example, 94410 + ... + 94423.

It is an arithmetic number, because the mean of its divisors is an integer number (377668).

2^1321831 is an apocalyptic number.

1321831 is a deficient number, since it is larger than the sum of its proper divisors (188841).

1321831 is an equidigital number, since it uses as much as digits as its factorization.

1321831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188840.

The product of its digits is 144, while the sum is 19.

The square root of 1321831 is about 1149.7090936406. The cubic root of 1321831 is about 109.7468282249.

The spelling of 1321831 in words is "one million, three hundred twenty-one thousand, eight hundred thirty-one".