129656816 has 20 divisors (see below), whose sum is σ = 252603624. Its totient is φ = 64468800.

The previous prime is 129656809. The next prime is 129656851. The reversal of 129656816 is 618656921.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19490 + ... + 25281.

Almost surely, 2^129656816 is an apocalyptic number.

129656816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

129656816 is a deficient number, since it is larger than the sum of its proper divisors (122946808).

129656816 is a wasteful number, since it uses less digits than its factorization.

129656816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44960 (or 44954 counting only the distinct ones).

The product of its digits is 155520, while the sum is 44.

The square root of 129656816 is about 11386.6946916127. The cubic root of 129656816 is about 506.1335397201.

The spelling of 129656816 in words is "one hundred twenty-nine million, six hundred fifty-six thousand, eight hundred sixteen".