129161 has 4 divisors (see below), whose sum is σ = 131652. Its totient is φ = 126672.

The previous prime is 129127. The next prime is 129169. The reversal of 129161 is 161921.

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 109561 + 19600 = 331^2 + 140^2 .

It is a cyclic number.

It is not a de Polignac number, because 129161 - 2⁶ = 129097 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 129161.

It is not an unprimeable number, because it can be changed into a prime (129169) 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, 1166 + ... + 1271.

It is an arithmetic number, because the mean of its divisors is an integer number (32913).

2¹²⁹¹⁶¹ is an apocalyptic number.

It is an amenable number.

129161 is a deficient number, since it is larger than the sum of its proper divisors (2491).

129161 is an equidigital number, since it uses as much as digits as its factorization.

129161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2490.

The product of its digits is 108, while the sum is 20.

The square root of 129161 is about 359.3897605664. The cubic root of 129161 is about 50.5487553189.

The spelling of 129161 in words is "one hundred twenty-nine thousand, one hundred sixty-one".