131940221 has 4 divisors (see below), whose sum is σ = 150788832. Its totient is φ = 113091612.

The previous prime is 131940209. The next prime is 131940251. The reversal of 131940221 is 122049131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122049131 = 157 ⋅777383.

It is a cyclic number.

It is not a de Polignac number, because 131940221 - 2²⁶ = 64831357 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 (131940251) 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, 9424295 + ... + 9424308.

It is an arithmetic number, because the mean of its divisors is an integer number (37697208).

Almost surely, 2^131940221 is an apocalyptic number.

It is an amenable number.

131940221 is a deficient number, since it is larger than the sum of its proper divisors (18848611).

131940221 is an equidigital number, since it uses as much as digits as its factorization.

131940221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18848610.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 131940221 is about 11486.5234514191. The cubic root of 131940221 is about 509.0874634034.

Adding to 131940221 its reverse (122049131), we get a palindrome (253989352).

The spelling of 131940221 in words is "one hundred thirty-one million, nine hundred forty thousand, two hundred twenty-one".