131221440423 has 20 divisors (see below), whose sum is σ = 198224658720. Its totient is φ = 86498023392.

The previous prime is 131221440353. The next prime is 131221440431. The reversal of 131221440423 is 324044122131.

131221440423 is a `hidden beast` number, since 1 + 31 + 221 + 4 + 404 + 2 + 3 = 666.

It is not a de Polignac number, because 131221440423 - 2⁸ = 131221440167 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131221440323) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 9094015 + ... + 9108432.

It is an arithmetic number, because the mean of its divisors is an integer number (9911232936).

Almost surely, 2^131221440423 is an apocalyptic number.

131221440423 is a deficient number, since it is larger than the sum of its proper divisors (67003218297).

131221440423 is an equidigital number, since it uses as much as digits as its factorization.

131221440423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18202548 (or 18202539 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

Adding to 131221440423 its reverse (324044122131), we get a palindrome (455265562554).

The spelling of 131221440423 in words is "one hundred thirty-one billion, two hundred twenty-one million, four hundred forty thousand, four hundred twenty-three".