129855091 has 4 divisors (see below), whose sum is σ = 130651912. Its totient is φ = 129058272.

The previous prime is 129855083. The next prime is 129855109. The reversal of 129855091 is 190558921.

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

It is a cyclic number.

It is not a de Polignac number, because 129855091 - 2³ = 129855083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129855041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 398166 + ... + 398491.

It is an arithmetic number, because the mean of its divisors is an integer number (32662978).

Almost surely, 2^129855091 is an apocalyptic number.

129855091 is a deficient number, since it is larger than the sum of its proper divisors (796821).

129855091 is an equidigital number, since it uses as much as digits as its factorization.

129855091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 796820.

The product of its (nonzero) digits is 32400, while the sum is 40.

The square root of 129855091 is about 11395.3977991117. The cubic root of 129855091 is about 506.3914063960.

The spelling of 129855091 in words is "one hundred twenty-nine million, eight hundred fifty-five thousand, ninety-one".