129445 has 4 divisors (see below), whose sum is σ = 155340. Its totient is φ = 103552.

The previous prime is 129443. The next prime is 129449. The reversal of 129445 is 544921.

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 91809 + 37636 = 303^2 + 194^2 .

It is a cyclic number.

It is not a de Polignac number, because 129445 - 2¹ = 129443 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12940 + ... + 12949.

It is an arithmetic number, because the mean of its divisors is an integer number (38835).

2¹²⁹⁴⁴⁵ is an apocalyptic number.

It is an amenable number.

129445 is a deficient number, since it is larger than the sum of its proper divisors (25895).

129445 is an equidigital number, since it uses as much as digits as its factorization.

129445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25894.

The product of its digits is 1440, while the sum is 25.

The square root of 129445 is about 359.7846578163. The cubic root of 129445 is about 50.5857771688.

The spelling of 129445 in words is "one hundred twenty-nine thousand, four hundred forty-five".