129617956 has 24 divisors (see below), whose sum is σ = 250885880. Its totient is φ = 58205952.

The previous prime is 129617941. The next prime is 129617959. The reversal of 129617956 is 659716921.

It can be written as a sum of positive squares in 4 ways, for example, as 341056 + 129276900 = 584^2 + 11370^2 .

It is not an unprimeable number, because it can be changed into a prime (129617959) 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 in 7 ways as a sum of consecutive naturals, for example, 31761 + ... + 35608.

Almost surely, 2^129617956 is an apocalyptic number.

It is an amenable number.

129617956 is a deficient number, since it is larger than the sum of its proper divisors (121267924).

129617956 is a wasteful number, since it uses less digits than its factorization.

129617956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67423 (or 67421 counting only the distinct ones).

The product of its digits is 204120, while the sum is 46.

The square root of 129617956 is about 11384.9881862038. The cubic root of 129617956 is about 506.0829695168.

It can be divided in two parts, 1296 and 17956, that multiplied together give a square (23270976 = 4824²).

The spelling of 129617956 in words is "one hundred twenty-nine million, six hundred seventeen thousand, nine hundred fifty-six".