129132865 has 4 divisors (see below), whose sum is σ = 154959444. Its totient is φ = 103306288.

The previous prime is 129132863. The next prime is 129132881. The reversal of 129132865 is 568231921.

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 91470096 + 37662769 = 9564^2 + 6137^2 .

It is a cyclic number.

It is not a de Polignac number, because 129132865 - 2¹ = 129132863 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129132863) 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, 12913282 + ... + 12913291.

It is an arithmetic number, because the mean of its divisors is an integer number (38739861).

Almost surely, 2^129132865 is an apocalyptic number.

It is an amenable number.

129132865 is a deficient number, since it is larger than the sum of its proper divisors (25826579).

129132865 is an equidigital number, since it uses as much as digits as its factorization.

129132865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25826578.

The product of its digits is 25920, while the sum is 37.

The square root of 129132865 is about 11363.6642417840. The cubic root of 129132865 is about 505.4508472562.

The spelling of 129132865 in words is "one hundred twenty-nine million, one hundred thirty-two thousand, eight hundred sixty-five".