129121712 has 20 divisors (see below), whose sum is σ = 256935936. Its totient is φ = 62815680.

The previous prime is 129121711. The next prime is 129121799. The reversal of 129121712 is 217121921.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (129121711) 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, 108464 + ... + 109647.

Almost surely, 2^129121712 is an apocalyptic number.

It is an amenable number.

129121712 is a deficient number, since it is larger than the sum of its proper divisors (127814224).

129121712 is a wasteful number, since it uses less digits than its factorization.

129121712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218156 (or 218150 counting only the distinct ones).

The product of its digits is 504, while the sum is 26.

The square root of 129121712 is about 11363.1735003915. The cubic root of 129121712 is about 505.4362951755.

The spelling of 129121712 in words is "one hundred twenty-nine million, one hundred twenty-one thousand, seven hundred twelve".