129261 has 8 divisors (see below), whose sum is σ = 188064. Its totient is φ = 78320.

The previous prime is 129229. The next prime is 129263. The reversal of 129261 is 162921.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 129261 - 2⁵ = 129229 is a prime.

It is a super-2 number, since 2×129261² = 33416812242, which contains 22 as substring.

129261 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129263) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1926 + ... + 1991.

It is an arithmetic number, because the mean of its divisors is an integer number (23508).

2¹²⁹²⁶¹ is an apocalyptic number.

129261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

129261 is a deficient number, since it is larger than the sum of its proper divisors (58803).

129261 is a wasteful number, since it uses less digits than its factorization.

129261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3931.

The product of its digits is 216, while the sum is 21.

The square root of 129261 is about 359.5288583688. The cubic root of 129261 is about 50.5617973661.

The spelling of 129261 in words is "one hundred twenty-nine thousand, two hundred sixty-one".