129972 has 12 divisors (see below), whose sum is σ = 303296. Its totient is φ = 43320.

The previous prime is 129971. The next prime is 130003. The reversal of 129972 is 279921.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129971) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5404 + ... + 5427.

2¹²⁹⁹⁷² is an apocalyptic number.

129972 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

129972 is an abundant number, since it is smaller than the sum of its proper divisors (173324).

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

129972 is a wasteful number, since it uses less digits than its factorization.

129972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10838 (or 10836 counting only the distinct ones).

The product of its digits is 2268, while the sum is 30.

The square root of 129972 is about 360.5162964416. The cubic root of 129972 is about 50.6543329474.

It can be divided in two parts, 1299 and 72, that multiplied together give a triangular number (93528 = T₄₃₂).

The spelling of 129972 in words is "one hundred twenty-nine thousand, nine hundred seventy-two".