331135220 has 54 divisors (see below), whose sum is σ = 755403138. Its totient is φ = 121874688.

The previous prime is 331135219. The next prime is 331135241. The reversal of 331135220 is 22531133.

It can be written as a sum of positive squares in 9 ways, for example, as 331094416 + 40804 = 18196^2 + 202^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 331135192 and 331135201.

It is a congruent number.

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 1057784 + ... + 1058096.

It is an arithmetic number, because the mean of its divisors is an integer number (13988947).

Almost surely, 2^331135220 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 331135220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (377701569).

331135220 is an abundant number, since it is smaller than the sum of its proper divisors (424267918).

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

331135220 is a wasteful number, since it uses less digits than its factorization.

331135220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661 (or 333 counting only the distinct ones).

The product of its (nonzero) digits is 540, while the sum is 20.

The square root of 331135220 is about 18197.1212008933. The cubic root of 331135220 is about 691.8338252460.

Multiplying 331135220 by its sum of digits (20), we get a square (6622704400 = 81380²).

331135220 divided by its sum of digits (20) gives a square (16556761 = 4069²).

Adding to 331135220 its reverse (22531133), we get a palindrome (353666353).

The spelling of 331135220 in words is "three hundred thirty-one million, one hundred thirty-five thousand, two hundred twenty".