311345221 has 6 divisors (see below), whose sum is σ = 342222566. Its totient is φ = 283041000.

The previous prime is 311345213. The next prime is 311345231. The reversal of 311345221 is 122543113.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 238857025 + 72488196 = 15455^2 + 8514^2 .

It is not a de Polignac number, because 311345221 - 2³ = 311345213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 311345192 and 311345201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311345231) 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 5 ways as a sum of consecutive naturals, for example, 1286430 + ... + 1286671.

Almost surely, 2^311345221 is an apocalyptic number.

It is an amenable number.

311345221 is a deficient number, since it is larger than the sum of its proper divisors (30877345).

311345221 is a wasteful number, since it uses less digits than its factorization.

311345221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2573123 (or 2573112 counting only the distinct ones).

The product of its digits is 720, while the sum is 22.

The square root of 311345221 is about 17644.9772173273. The cubic root of 311345221 is about 677.7674917656.

Adding to 311345221 its reverse (122543113), we get a palindrome (433888334).

The spelling of 311345221 in words is "three hundred eleven million, three hundred forty-five thousand, two hundred twenty-one".