129978907 has 4 divisors (see below), whose sum is σ = 130018336. Its totient is φ = 129939480.

The previous prime is 129978883. The next prime is 129978941. The reversal of 129978907 is 709879921.

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-129978907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129978967) 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 3 ways as a sum of consecutive naturals, for example, 14268 + ... + 21529.

It is an arithmetic number, because the mean of its divisors is an integer number (32504584).

Almost surely, 2^129978907 is an apocalyptic number.

129978907 is a deficient number, since it is larger than the sum of its proper divisors (39429).

129978907 is an equidigital number, since it uses as much as digits as its factorization.

129978907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39428.

The product of its (nonzero) digits is 571536, while the sum is 52.

The square root of 129978907 is about 11400.8292242275. The cubic root of 129978907 is about 506.5523022598.

It can be divided in two parts, 12997 and 8907, that added together give a square (21904 = 148²).

The spelling of 129978907 in words is "one hundred twenty-nine million, nine hundred seventy-eight thousand, nine hundred seven".