129139278 has 16 divisors (see below), whose sum is σ = 258670416. Its totient is φ = 42981120.

The previous prime is 129139261. The next prime is 129139279. The reversal of 129139278 is 872931921.

It is a super-2 number, since 2×129139278² = 33353906244722568, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129139279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11953 + ... + 20028.

It is an arithmetic number, because the mean of its divisors is an integer number (16166901).

Almost surely, 2^129139278 is an apocalyptic number.

129139278 is an abundant number, since it is smaller than the sum of its proper divisors (129531138).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129139278 is a wasteful number, since it uses less digits than its factorization.

129139278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32659.

The product of its digits is 54432, while the sum is 42.

The square root of 129139278 is about 11363.9464095885. The cubic root of 129139278 is about 505.4592143558.

The spelling of 129139278 in words is "one hundred twenty-nine million, one hundred thirty-nine thousand, two hundred seventy-eight".