129012779 has 12 divisors (see below), whose sum is σ = 156628944. Its totient is φ = 104075904.

The previous prime is 129012757. The next prime is 129012803. The reversal of 129012779 is 977210921.

It is a de Polignac number, because none of the positive numbers 2^k-129012779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129012379) 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 11 ways as a sum of consecutive naturals, for example, 29864 + ... + 33909.

It is an arithmetic number, because the mean of its divisors is an integer number (13052412).

Almost surely, 2^129012779 is an apocalyptic number.

129012779 is a deficient number, since it is larger than the sum of its proper divisors (27616165).

129012779 is an equidigital number, since it uses as much as digits as its factorization.

129012779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63814 (or 63797 counting only the distinct ones).

The product of its (nonzero) digits is 15876, while the sum is 38.

The square root of 129012779 is about 11358.3792417757. The cubic root of 129012779 is about 505.2941187703.

The spelling of 129012779 in words is "one hundred twenty-nine million, twelve thousand, seven hundred seventy-nine".