129707891 has 4 divisors (see below), whose sum is σ = 129747000. Its totient is φ = 129668784.

The previous prime is 129707863. The next prime is 129707911. The reversal of 129707891 is 198707921.

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-129707891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129707821) 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, 14066 + ... + 21383.

It is an arithmetic number, because the mean of its divisors is an integer number (32436750).

Almost surely, 2^129707891 is an apocalyptic number.

129707891 is a deficient number, since it is larger than the sum of its proper divisors (39109).

129707891 is an equidigital number, since it uses as much as digits as its factorization.

129707891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39108.

The product of its (nonzero) digits is 63504, while the sum is 44.

The square root of 129707891 is about 11388.9372199516. The cubic root of 129707891 is about 506.1999904672.

The spelling of 129707891 in words is "one hundred twenty-nine million, seven hundred seven thousand, eight hundred ninety-one".