129189888 has 144 divisors (see below), whose sum is σ = 384143760. Its totient is φ = 41803776.

The previous prime is 129189871. The next prime is 129189889. The reversal of 129189888 is 888981921.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×129189888² = 33380054322905088, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (129189889) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 792495 + ... + 792657.

It is an arithmetic number, because the mean of its divisors is an integer number (2667665).

Almost surely, 2^129189888 is an apocalyptic number.

129189888 is a gapful number since it is divisible by the number (18) 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 129189888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (192071880).

129189888 is an abundant number, since it is smaller than the sum of its proper divisors (254953872).

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

129189888 is a wasteful number, since it uses less digits than its factorization.

129189888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234 (or 211 counting only the distinct ones).

The product of its digits is 663552, while the sum is 54.

The square root of 129189888 is about 11366.1729707057. The cubic root of 129189888 is about 505.5252359674.

The spelling of 129189888 in words is "one hundred twenty-nine million, one hundred eighty-nine thousand, eight hundred eighty-eight".