131221232 has 40 divisors (see below), whose sum is σ = 269978256. Its totient is φ = 61572096.

The previous prime is 131221231. The next prime is 131221247. The reversal of 131221232 is 232122131.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a self number, because there is not a number n which added to its sum of digits gives 131221232.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131221231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 166343 + ... + 167129.

Almost surely, 2^131221232 is an apocalyptic number.

It is an amenable number.

131221232 is an abundant number, since it is smaller than the sum of its proper divisors (138757024).

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

131221232 is a wasteful number, since it uses less digits than its factorization.

131221232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1425 (or 1419 counting only the distinct ones).

The product of its digits is 144, while the sum is 17.

The square root of 131221232 is about 11455.1836301301. The cubic root of 131221232 is about 508.1610459288.

Adding to 131221232 its reverse (232122131), we get a palindrome (363343363).

The spelling of 131221232 in words is "one hundred thirty-one million, two hundred twenty-one thousand, two hundred thirty-two".