311143221 has 32 divisors (see below), whose sum is σ = 486460800. Its totient is φ = 196007040.

The previous prime is 311143193. The next prime is 311143223. The reversal of 311143221 is 122341113.

It is not a de Polignac number, because 311143221 - 2⁷ = 311143093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 311143194 and 311143203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311143223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 389995 + ... + 390791.

It is an arithmetic number, because the mean of its divisors is an integer number (15201900).

Almost surely, 2^311143221 is an apocalyptic number.

It is an amenable number.

311143221 is a deficient number, since it is larger than the sum of its proper divisors (175317579).

311143221 is a wasteful number, since it uses less digits than its factorization.

311143221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1586 (or 1580 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 311143221 is about 17639.2522800713. The cubic root of 311143221 is about 677.6208821037.

Adding to 311143221 its reverse (122341113), we get a palindrome (433484334).

It can be divided in two parts, 311143 and 221, that added together give a square (311364 = 558²).

The spelling of 311143221 in words is "three hundred eleven million, one hundred forty-three thousand, two hundred twenty-one".