131333221 has 4 divisors (see below), whose sum is σ = 131357772. Its totient is φ = 131308672.

The previous prime is 131333203. The next prime is 131333227. The reversal of 131333221 is 122333131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122333131 = 127 ⋅963253.

It can be written as a sum of positive squares in 2 ways, for example, as 74632321 + 56700900 = 8639^2 + 7530^2 .

It is a cyclic number.

It is not a de Polignac number, because 131333221 - 2¹⁵ = 131300453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131333227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 460 + ... + 16213.

It is an arithmetic number, because the mean of its divisors is an integer number (32839443).

Almost surely, 2^131333221 is an apocalyptic number.

It is an amenable number.

131333221 is a deficient number, since it is larger than the sum of its proper divisors (24551).

131333221 is an equidigital number, since it uses as much as digits as its factorization.

131333221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24550.

The product of its digits is 324, while the sum is 19.

The square root of 131333221 is about 11460.0707240401. The cubic root of 131333221 is about 508.3055658994.

Adding to 131333221 its reverse (122333131), we get a palindrome (253666352).

The spelling of 131333221 in words is "one hundred thirty-one million, three hundred thirty-three thousand, two hundred twenty-one".