131445 has 24 divisors (see below), whose sum is σ = 239616. Its totient is φ = 66528.

The previous prime is 131441. The next prime is 131447. The reversal of 131445 is 544131.

It is a happy number.

It is not a de Polignac number, because 131445 - 2² = 131441 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 972 + ... + 1098.

It is an arithmetic number, because the mean of its divisors is an integer number (9984).

2¹³¹⁴⁴⁵ is an apocalyptic number.

131445 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

131445 is a deficient number, since it is larger than the sum of its proper divisors (108171).

131445 is a wasteful number, since it uses less digits than its factorization.

131445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161 (or 158 counting only the distinct ones).

The product of its digits is 240, while the sum is 18.

The square root of 131445 is about 362.5534443361. The cubic root of 131445 is about 50.8449732967.

Adding to 131445 its reverse (544131), we get a palindrome (675576).

Subtracting 131445 from its reverse (544131), we obtain a triangular number (412686 = T₉₀₈).

It can be divided in two parts, 131 and 445, that added together give a square (576 = 24²).

The spelling of 131445 in words is "one hundred thirty-one thousand, four hundred forty-five".