129978166 has 16 divisors (see below), whose sum is σ = 198387504. Its totient is φ = 63857664.

The previous prime is 129978161. The next prime is 129978169. The reversal of 129978166 is 661879921.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129978161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30010 + ... + 34066.

It is an arithmetic number, because the mean of its divisors is an integer number (12399219).

Almost surely, 2^129978166 is an apocalyptic number.

129978166 is a deficient number, since it is larger than the sum of its proper divisors (68409338).

129978166 is a wasteful number, since it uses less digits than its factorization.

129978166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4335.

The product of its digits is 326592, while the sum is 49.

The square root of 129978166 is about 11400.7967265450. The cubic root of 129978166 is about 506.5513396524.

The spelling of 129978166 in words is "one hundred twenty-nine million, nine hundred seventy-eight thousand, one hundred sixty-six".