129755 has 4 divisors (see below), whose sum is σ = 155712. Its totient is φ = 103800.

The previous prime is 129749. The next prime is 129757. The reversal of 129755 is 557921.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 129755 - 2⁸ = 129499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129757) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12971 + ... + 12980.

It is an arithmetic number, because the mean of its divisors is an integer number (38928).

2¹²⁹⁷⁵⁵ is an apocalyptic number.

129755 is a deficient number, since it is larger than the sum of its proper divisors (25957).

129755 is an equidigital number, since it uses as much as digits as its factorization.

129755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25956.

The product of its digits is 3150, while the sum is 29.

The square root of 129755 is about 360.2152134488. The cubic root of 129755 is about 50.6261265816.

The spelling of 129755 in words is "one hundred twenty-nine thousand, seven hundred fifty-five".