131031200001221 has 4 divisors (see below), whose sum is σ = 141110523078252. Its totient is φ = 120951876924192.

The previous prime is 131031200001187. The next prime is 131031200001239. The reversal of 131031200001221 is 122100002130131.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 47729983698721 + 83301216302500 = 6908689^2 + 9126950^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131031200001221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 131031200001221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131031200001241) 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, 5039661538496 + ... + 5039661538521.

It is an arithmetic number, because the mean of its divisors is an integer number (35277630769563).

Almost surely, 2^{131031200001221} is an apocalyptic number.

It is an amenable number.

131031200001221 is a deficient number, since it is larger than the sum of its proper divisors (10079323077031).

131031200001221 is a wasteful number, since it uses less digits than its factorization.

131031200001221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10079323077030.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 131031200001221 its reverse (122100002130131), we get a palindrome (253131202131352).

The spelling of 131031200001221 in words is "one hundred thirty-one trillion, thirty-one billion, two hundred million, one thousand, two hundred twenty-one".