129777506 has 16 divisors (see below), whose sum is σ = 196732800. Its totient is φ = 64203888.

The previous prime is 129777499. The next prime is 129777509. The reversal of 129777506 is 605777921.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (129777509) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 81191 + ... + 82773.

It is an arithmetic number, because the mean of its divisors is an integer number (12295800).

Almost surely, 2^129777506 is an apocalyptic number.

129777506 is a deficient number, since it is larger than the sum of its proper divisors (66955294).

129777506 is a wasteful number, since it uses less digits than its factorization.

129777506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1993.

The product of its (nonzero) digits is 185220, while the sum is 44.

The square root of 129777506 is about 11391.9930653069. The cubic root of 129777506 is about 506.2905344570.

The spelling of 129777506 in words is "one hundred twenty-nine million, seven hundred seventy-seven thousand, five hundred six".