129717756 has 72 divisors (see below), whose sum is σ = 383487104. Its totient is φ = 36197280.

The previous prime is 129717743. The next prime is 129717773. The reversal of 129717756 is 657717921.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 4851 + ... + 16821.

Almost surely, 2^129717756 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129717756, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (191743552).

129717756 is an abundant number, since it is smaller than the sum of its proper divisors (253769348).

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

129717756 is a wasteful number, since it uses less digits than its factorization.

129717756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12031 (or 12026 counting only the distinct ones).

The product of its digits is 185220, while the sum is 45.

The square root of 129717756 is about 11389.3703074402. The cubic root of 129717756 is about 506.2128232416.

The spelling of 129717756 in words is "one hundred twenty-nine million, seven hundred seventeen thousand, seven hundred fifty-six".