321311231 has 4 divisors (see below), whose sum is σ = 321393864. Its totient is φ = 321228600.

The previous prime is 321311209. The next prime is 321311233. The reversal of 321311231 is 132113123.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 132113123 = 109 ⋅1212047.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321311231 is a prime.

It is a super-2 number, since 2×321311231² = 206481814333470722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321311233) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35180 + ... + 43361.

It is an arithmetic number, because the mean of its divisors is an integer number (80348466).

Almost surely, 2^321311231 is an apocalyptic number.

321311231 is a deficient number, since it is larger than the sum of its proper divisors (82633).

321311231 is an equidigital number, since it uses as much as digits as its factorization.

321311231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82632.

The product of its digits is 108, while the sum is 17.

The square root of 321311231 is about 17925.1563730976. The cubic root of 321311231 is about 684.9233444688.

Adding to 321311231 its reverse (132113123), we get a palindrome (453424354).

The spelling of 321311231 in words is "three hundred twenty-one million, three hundred eleven thousand, two hundred thirty-one".