129081312 has 36 divisors (see below), whose sum is σ = 367075800. Its totient is φ = 43027008.

The previous prime is 129081283. The next prime is 129081319. The reversal of 129081312 is 213180921.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129081319) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 223812 + ... + 224387.

It is an arithmetic number, because the mean of its divisors is an integer number (10196550).

Almost surely, 2^129081312 is an apocalyptic number.

129081312 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

129081312 is an abundant number, since it is smaller than the sum of its proper divisors (237994488).

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

129081312 is a wasteful number, since it uses less digits than its factorization.

129081312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448215 (or 448204 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 129081312 is about 11361.3956889108. The cubic root of 129081312 is about 505.3835755205.

The spelling of 129081312 in words is "one hundred twenty-nine million, eighty-one thousand, three hundred twelve".