131220324 has 30 divisors (see below), whose sum is σ = 343036694. Its totient is φ = 43740000.

The previous prime is 131220293. The next prime is 131220329. The reversal of 131220324 is 423022131.

It can be written as a sum of positive squares in only one way, i.e., 126157824 + 5062500 = 11232^2 + 2250^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 131220297 and 131220306.

It is not an unprimeable number, because it can be changed into a prime (131220329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 202177 + ... + 202824.

Almost surely, 2^131220324 is an apocalyptic number.

It is an amenable number.

131220324 is an abundant number, since it is smaller than the sum of its proper divisors (211816370).

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

131220324 is a wasteful number, since it uses less digits than its factorization.

131220324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405017 (or 405006 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 131220324 is about 11455.1439973490. The cubic root of 131220324 is about 508.1598738336.

Adding to 131220324 its reverse (423022131), we get a palindrome (554242455).

The spelling of 131220324 in words is "one hundred thirty-one million, two hundred twenty thousand, three hundred twenty-four".