129972336 has 80 divisors (see below), whose sum is σ = 373309440. Its totient is φ = 38695680.

The previous prime is 129972329. The next prime is 129972341. The reversal of 129972336 is 633279921.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15985 + ... + 22703.

It is an arithmetic number, because the mean of its divisors is an integer number (4666368).

Almost surely, 2^129972336 is an apocalyptic number.

129972336 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 129972336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (186654720).

129972336 is an abundant number, since it is smaller than the sum of its proper divisors (243337104).

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

129972336 is a wasteful number, since it uses less digits than its factorization.

129972336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6774 (or 6768 counting only the distinct ones).

The product of its digits is 122472, while the sum is 42.

The square root of 129972336 is about 11400.5410397928. The cubic root of 129972336 is about 506.5437659741.

The spelling of 129972336 in words is "one hundred twenty-nine million, nine hundred seventy-two thousand, three hundred thirty-six".