3131131220 has 192 divisors, whose sum is σ = 8399462400. Its totient is φ = 955722240.

The previous prime is 3131131193. The next prime is 3131131249. The reversal of 3131131220 is 221311313.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3731561 + ... + 3732399.

It is an arithmetic number, because the mean of its divisors is an integer number (43747200).

Almost surely, 2^3131131220 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 3131131220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4199731200).

3131131220 is an abundant number, since it is smaller than the sum of its proper divisors (5268331180).

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

3131131220 is a wasteful number, since it uses less digits than its factorization.

3131131220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 958 (or 956 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 3131131220 is about 55956.5118641253. The cubic root of 3131131220 is about 1462.9643935906.

Adding to 3131131220 its reverse (221311313), we get a palindrome (3352442533).

The spelling of 3131131220 in words is "three billion, one hundred thirty-one million, one hundred thirty-one thousand, two hundred twenty".