131320421 has 4 divisors (see below), whose sum is σ = 131347500. Its totient is φ = 131293344.

The previous prime is 131320411. The next prime is 131320447. The reversal of 131320421 is 124023131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 124023131 = 73 ⋅1698947.

It can be written as a sum of positive squares in 2 ways, for example, as 43692100 + 87628321 = 6610^2 + 9361^2 .

It is a cyclic number.

It is not a de Polignac number, because 131320421 - 2¹⁴ = 131304037 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 131320421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131320411) 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, 4046 + ... + 16703.

It is an arithmetic number, because the mean of its divisors is an integer number (32836875).

Almost surely, 2^131320421 is an apocalyptic number.

It is an amenable number.

131320421 is a deficient number, since it is larger than the sum of its proper divisors (27079).

131320421 is an equidigital number, since it uses as much as digits as its factorization.

131320421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27078.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 131320421 is about 11459.5122496553. The cubic root of 131320421 is about 508.2890518685.

Adding to 131320421 its reverse (124023131), we get a palindrome (255343552).

The spelling of 131320421 in words is "one hundred thirty-one million, three hundred twenty thousand, four hundred twenty-one".