129696779 has 4 divisors (see below), whose sum is σ = 129725376. Its totient is φ = 129668184.

The previous prime is 129696751. The next prime is 129696781. The reversal of 129696779 is 977696921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 977696921 = 14683 ⋅66587.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129696779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129696799) 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 3 ways as a sum of consecutive naturals, for example, 5819 + ... + 17124.

It is an arithmetic number, because the mean of its divisors is an integer number (32431344).

Almost surely, 2^129696779 is an apocalyptic number.

129696779 is a deficient number, since it is larger than the sum of its proper divisors (28597).

129696779 is an equidigital number, since it uses as much as digits as its factorization.

129696779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28596.

The product of its digits is 2571912, while the sum is 56.

The square root of 129696779 is about 11388.4493676707. The cubic root of 129696779 is about 506.1855347676.

The spelling of 129696779 in words is "one hundred twenty-nine million, six hundred ninety-six thousand, seven hundred seventy-nine".