311128225 has 6 divisors (see below), whose sum is σ = 385799030. Its totient is φ = 248902560.

The previous prime is 311128201. The next prime is 311128231. The reversal of 311128225 is 522821113.

It can be written as a sum of positive squares in 3 ways, for example, as 2634129 + 308494096 = 1623^2 + 17564^2 .

It is not a de Polignac number, because 311128225 - 2¹⁷ = 310997153 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 12445129 = 311128225 / (3 + 1 + 1 + 1 + 2 + 8 + 2 + 2 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 311128225.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6222540 + ... + 6222589.

Almost surely, 2^311128225 is an apocalyptic number.

It is an amenable number.

311128225 is a deficient number, since it is larger than the sum of its proper divisors (74670805).

311128225 is a wasteful number, since it uses less digits than its factorization.

311128225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12445139 (or 12445134 counting only the distinct ones).

The product of its digits is 960, while the sum is 25.

The square root of 311128225 is about 17638.8272002421. The cubic root of 311128225 is about 677.6099956209.

Adding to 311128225 its reverse (522821113), we get a palindrome (833949338).

The spelling of 311128225 in words is "three hundred eleven million, one hundred twenty-eight thousand, two hundred twenty-five".