129681568 has 12 divisors (see below), whose sum is σ = 255310650. Its totient is φ = 64840768.

The previous prime is 129681553. The next prime is 129681569. The reversal of 129681568 is 865186921.

It can be written as a sum of positive squares in only one way, i.e., 111260304 + 18421264 = 10548^2 + 4292^2 .

It is not an unprimeable number, because it can be changed into a prime (129681569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2026243 + ... + 2026306.

Almost surely, 2^129681568 is an apocalyptic number.

It is an amenable number.

129681568 is a deficient number, since it is larger than the sum of its proper divisors (125629082).

129681568 is an equidigital number, since it uses as much as digits as its factorization.

129681568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4052559 (or 4052551 counting only the distinct ones).

The product of its digits is 207360, while the sum is 46.

The square root of 129681568 is about 11387.7815223159. The cubic root of 129681568 is about 506.1657453037.

The spelling of 129681568 in words is "one hundred twenty-nine million, six hundred eighty-one thousand, five hundred sixty-eight".