131221203123 has 16 divisors (see below), whose sum is σ = 183279038976. Its totient is φ = 83351685120.

The previous prime is 131221203067. The next prime is 131221203161. The reversal of 131221203123 is 321302122131.

It is not a de Polignac number, because 131221203123 - 2⁸ = 131221202867 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 131221203123.

It is not an unprimeable number, because it can be changed into a prime (131221203193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3682183 + ... + 3717648.

It is an arithmetic number, because the mean of its divisors is an integer number (11454939936).

Almost surely, 2^131221203123 is an apocalyptic number.

131221203123 is a deficient number, since it is larger than the sum of its proper divisors (52057835853).

131221203123 is a wasteful number, since it uses less digits than its factorization.

131221203123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7400114.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 131221203123 its reverse (321302122131), we get a palindrome (452523325254).

The spelling of 131221203123 in words is "one hundred thirty-one billion, two hundred twenty-one million, two hundred three thousand, one hundred twenty-three".