131631421 has 4 divisors (see below), whose sum is σ = 131665212. Its totient is φ = 131597632.

The previous prime is 131631413. The next prime is 131631427. The reversal of 131631421 is 124136131.

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 118592100 + 13039321 = 10890^2 + 3611^2 .

It is a cyclic number.

It is not a de Polignac number, because 131631421 - 2³ = 131631413 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 131631392 and 131631401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131631427) 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, 10156 + ... + 19141.

It is an arithmetic number, because the mean of its divisors is an integer number (32916303).

Almost surely, 2^131631421 is an apocalyptic number.

It is an amenable number.

131631421 is a deficient number, since it is larger than the sum of its proper divisors (33791).

131631421 is an equidigital number, since it uses as much as digits as its factorization.

131631421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33790.

The product of its digits is 432, while the sum is 22.

The square root of 131631421 is about 11473.0737381052. The cubic root of 131631421 is about 508.6899879107.

Adding to 131631421 its reverse (124136131), we get a palindrome (255767552).

The spelling of 131631421 in words is "one hundred thirty-one million, six hundred thirty-one thousand, four hundred twenty-one".