129028291 has 4 divisors (see below), whose sum is σ = 147460912. Its totient is φ = 110595672.

The previous prime is 129028253. The next prime is 129028309. The reversal of 129028291 is 192820921.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129028291 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129028591) 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, 9216300 + ... + 9216313.

It is an arithmetic number, because the mean of its divisors is an integer number (36865228).

Almost surely, 2^129028291 is an apocalyptic number.

129028291 is a deficient number, since it is larger than the sum of its proper divisors (18432621).

129028291 is an equidigital number, since it uses as much as digits as its factorization.

129028291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18432620.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 129028291 is about 11359.0620651531. The cubic root of 129028291 is about 505.3143694987.

The spelling of 129028291 in words is "one hundred twenty-nine million, twenty-eight thousand, two hundred ninety-one".