311201220 has 96 divisors (see below), whose sum is σ = 960575616. Its totient is φ = 74649600.

The previous prime is 311201207. The next prime is 311201237. The reversal of 311201220 is 22102113.

311201220 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 311201196 and 311201205.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 61590 + ... + 66450.

It is an arithmetic number, because the mean of its divisors is an integer number (10005996).

Almost surely, 2^311201220 is an apocalyptic number.

311201220 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 311201220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (480287808).

311201220 is an abundant number, since it is smaller than the sum of its proper divisors (649374396).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

311201220 is a wasteful number, since it uses less digits than its factorization.

311201220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4981 (or 4979 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 311201220 is about 17640.8962357359. The cubic root of 311201220 is about 677.6629837139.

Adding to 311201220 its reverse (22102113), we get a palindrome (333303333).

The spelling of 311201220 in words is "three hundred eleven million, two hundred one thousand, two hundred twenty".