131531224 has 64 divisors (see below), whose sum is σ = 286473600. Its totient is φ = 55987200.

The previous prime is 131531221. The next prime is 131531249. The reversal of 131531224 is 422135131.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 131531195 and 131531204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131531221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 161779 + ... + 162589.

It is an arithmetic number, because the mean of its divisors is an integer number (4476150).

Almost surely, 2^131531224 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 131531224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143236800).

131531224 is an abundant number, since it is smaller than the sum of its proper divisors (154942376).

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

131531224 is a wasteful number, since it uses less digits than its factorization.

131531224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 944 (or 940 counting only the distinct ones).

The product of its digits is 720, while the sum is 22.

The square root of 131531224 is about 11468.7062914698. The cubic root of 131531224 is about 508.5608846204.

Adding to 131531224 its reverse (422135131), we get a palindrome (553666355).

The spelling of 131531224 in words is "one hundred thirty-one million, five hundred thirty-one thousand, two hundred twenty-four".