131223201221 has 16 divisors (see below), whose sum is σ = 157727996928. Its totient is φ = 106794979200.

The previous prime is 131223201191. The next prime is 131223201247. The reversal of 131223201221 is 122102322131.

It is not a de Polignac number, because 131223201221 - 2³⁴ = 114043332037 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 131223201193 and 131223201202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131223201521) 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, 5693360 + ... + 5716361.

It is an arithmetic number, because the mean of its divisors is an integer number (9857999808).

Almost surely, 2^131223201221 is an apocalyptic number.

It is an amenable number.

131223201221 is a deficient number, since it is larger than the sum of its proper divisors (26504795707).

131223201221 is a wasteful number, since it uses less digits than its factorization.

131223201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11409812.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 131223201221 its reverse (122102322131), we get a palindrome (253325523352).

The spelling of 131223201221 in words is "one hundred thirty-one billion, two hundred twenty-three million, two hundred one thousand, two hundred twenty-one".