129280885 has 4 divisors (see below), whose sum is σ = 155137068. Its totient is φ = 103424704.

The previous prime is 129280873. The next prime is 129280891. The reversal of 129280885 is 588082921.

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 25220484 + 104060401 = 5022^2 + 10201^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129280885 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12928084 + ... + 12928093.

It is an arithmetic number, because the mean of its divisors is an integer number (38784267).

Almost surely, 2^129280885 is an apocalyptic number.

It is an amenable number.

129280885 is a deficient number, since it is larger than the sum of its proper divisors (25856183).

129280885 is an equidigital number, since it uses as much as digits as its factorization.

129280885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25856182.

The product of its (nonzero) digits is 92160, while the sum is 43.

The square root of 129280885 is about 11370.1752405141. The cubic root of 129280885 is about 505.6438997531.

The spelling of 129280885 in words is "one hundred twenty-nine million, two hundred eighty thousand, eight hundred eighty-five".