129928 has 16 divisors (see below), whose sum is σ = 247500. Its totient is φ = 63936.

The previous prime is 129919. The next prime is 129937. The reversal of 129928 is 829921.

It is an interprime number because it is at equal distance from previous prime (129919) and next prime (129937).

It can be written as a sum of positive squares in 2 ways, for example, as 128164 + 1764 = 358^2 + 42^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 129928.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 798 + ... + 946.

2¹²⁹⁹²⁸ is an apocalyptic number.

It is an amenable number.

129928 is a deficient number, since it is larger than the sum of its proper divisors (117572).

129928 is a wasteful number, since it uses less digits than its factorization.

129928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264 (or 260 counting only the distinct ones).

The product of its digits is 2592, while the sum is 31.

The square root of 129928 is about 360.4552676824. The cubic root of 129928 is about 50.6486162233.

It can be divided in two parts, 1 and 29928, that added together give a square (29929 = 173²).

The spelling of 129928 in words is "one hundred twenty-nine thousand, nine hundred twenty-eight".