131220120321 has 12 divisors (see below), whose sum is σ = 189544088448. Its totient is φ = 87478273464.

The previous prime is 131220120313. The next prime is 131220120323. The reversal of 131220120321 is 123021022131.

131220120321 is a `hidden beast` number, since 1 + 3 + 1 + 220 + 120 + 321 = 666.

It is not a de Polignac number, because 131220120321 - 2³ = 131220120313 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 131220120294 and 131220120303.

It is not an unprimeable number, because it can be changed into a prime (131220120323) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 425356 + ... + 665858.

It is an arithmetic number, because the mean of its divisors is an integer number (15795340704).

Almost surely, 2^131220120321 is an apocalyptic number.

It is an amenable number.

131220120321 is a deficient number, since it is larger than the sum of its proper divisors (58323968127).

131220120321 is a wasteful number, since it uses less digits than its factorization.

131220120321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301132 (or 301129 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 131220120321 its reverse (123021022131), we get a palindrome (254241142452).

The spelling of 131220120321 in words is "one hundred thirty-one billion, two hundred twenty million, one hundred twenty thousand, three hundred twenty-one".