129123696 has 80 divisors (see below), whose sum is σ = 378170240. Its totient is φ = 37635840.

The previous prime is 129123661. The next prime is 129123713. The reversal of 129123696 is 696321921.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 6411 + ... + 17301.

It is an arithmetic number, because the mean of its divisors is an integer number (4727128).

Almost surely, 2^129123696 is an apocalyptic number.

129123696 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129123696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (189085120).

129123696 is an abundant number, since it is smaller than the sum of its proper divisors (249046544).

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

129123696 is a wasteful number, since it uses less digits than its factorization.

129123696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10934 (or 10928 counting only the distinct ones).

The product of its digits is 34992, while the sum is 39.

The square root of 129123696 is about 11363.2607996121. The cubic root of 129123696 is about 505.4388838971.

The spelling of 129123696 in words is "one hundred twenty-nine million, one hundred twenty-three thousand, six hundred ninety-six".