1311231 has 4 divisors (see below), whose sum is σ = 1748312. Its totient is φ = 874152.

The previous prime is 1311229. The next prime is 1311239. The reversal of 1311231 is 1321131.

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

It is not a de Polignac number, because 1311231 - 2¹ = 1311229 is a prime.

It is a super-2 number, since 2×1311231² = 3438653470722, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

1311231 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311239) 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, 218536 + ... + 218541.

It is an arithmetic number, because the mean of its divisors is an integer number (437078).

2^1311231 is an apocalyptic number.

1311231 is a deficient number, since it is larger than the sum of its proper divisors (437081).

1311231 is an equidigital number, since it uses as much as digits as its factorization.

1311231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437080.

The product of its digits is 18, while the sum is 12.

The square root of 1311231 is about 1145.0899527985. The cubic root of 1311231 is about 109.4526807074.

Adding to 1311231 its reverse (1321131), we get a palindrome (2632362).

The spelling of 1311231 in words is "one million, three hundred eleven thousand, two hundred thirty-one".