129857979 has 8 divisors (see below), whose sum is σ = 177170752. Its totient is φ = 84558600.

The previous prime is 129857957. The next prime is 129858007. The reversal of 129857979 is 979758921.

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

It is not a de Polignac number, because 129857979 - 2¹⁵ = 129825211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129857279) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 503197 + ... + 503454.

It is an arithmetic number, because the mean of its divisors is an integer number (22146344).

Almost surely, 2^129857979 is an apocalyptic number.

129857979 is a deficient number, since it is larger than the sum of its proper divisors (47312773).

129857979 is a wasteful number, since it uses less digits than its factorization.

129857979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1006697.

The product of its digits is 2857680, while the sum is 57.

The square root of 129857979 is about 11395.5245162300. The cubic root of 129857979 is about 506.3951604461.

The spelling of 129857979 in words is "one hundred twenty-nine million, eight hundred fifty-seven thousand, nine hundred seventy-nine".