313212221 has 4 divisors (see below), whose sum is σ = 357956832. Its totient is φ = 268467612.

The previous prime is 313212077. The next prime is 313212227. The reversal of 313212221 is 122212313.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122212313 = 19 ⋅6432227.

It is not a de Polignac number, because 313212221 - 2²⁶ = 246103357 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 313212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (313212227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22372295 + ... + 22372308.

It is an arithmetic number, because the mean of its divisors is an integer number (89489208).

Almost surely, 2^313212221 is an apocalyptic number.

It is an amenable number.

313212221 is a deficient number, since it is larger than the sum of its proper divisors (44744611).

313212221 is an equidigital number, since it uses as much as digits as its factorization.

313212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44744610.

The product of its digits is 144, while the sum is 17.

The square root of 313212221 is about 17697.8027167216. The cubic root of 313212221 is about 679.1195503834.

Adding to 313212221 its reverse (122212313), we get a palindrome (435424534).

The spelling of 313212221 in words is "three hundred thirteen million, two hundred twelve thousand, two hundred twenty-one".