129923857 has 8 divisors (see below), whose sum is σ = 153604800. Its totient is φ = 107523024.

The previous prime is 129923831. The next prime is 129923861. The reversal of 129923857 is 758329921.

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

It is a de Polignac number, because none of the positive numbers 2^k-129923857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129929857) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 319807 + ... + 320212.

It is an arithmetic number, because the mean of its divisors is an integer number (19200600).

Almost surely, 2^129923857 is an apocalyptic number.

It is an amenable number.

129923857 is a deficient number, since it is larger than the sum of its proper divisors (23680943).

129923857 is an equidigital number, since it uses as much as digits as its factorization.

129923857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 640055.

The product of its digits is 272160, while the sum is 46.

The square root of 129923857 is about 11398.4146704706. The cubic root of 129923857 is about 506.4807787523.

The spelling of 129923857 in words is "one hundred twenty-nine million, nine hundred twenty-three thousand, eight hundred fifty-seven".