129427 has 4 divisors (see below), whose sum is σ = 133920. Its totient is φ = 124936.

The previous prime is 129419. The next prime is 129439. The reversal of 129427 is 724921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 724921 = 41 ⋅17681.

It is a cyclic number.

It is not a de Polignac number, because 129427 - 2³ = 129419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129457) 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, 2203 + ... + 2260.

It is an arithmetic number, because the mean of its divisors is an integer number (33480).

2¹²⁹⁴²⁷ is an apocalyptic number.

129427 is a deficient number, since it is larger than the sum of its proper divisors (4493).

129427 is an equidigital number, since it uses as much as digits as its factorization.

129427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4492.

The product of its digits is 1008, while the sum is 25.

The square root of 129427 is about 359.7596419834. The cubic root of 129427 is about 50.5834323217.

The spelling of 129427 in words is "one hundred twenty-nine thousand, four hundred twenty-seven".