129641729 has 4 divisors (see below), whose sum is σ = 148161984. Its totient is φ = 111121476.

The previous prime is 129641663. The next prime is 129641737. The reversal of 129641729 is 927146921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 927146921 = 1451 ⋅638971.

It is a cyclic number.

It is not a de Polignac number, because 129641729 - 2¹² = 129637633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129641749) 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, 9260117 + ... + 9260130.

It is an arithmetic number, because the mean of its divisors is an integer number (37040496).

Almost surely, 2^129641729 is an apocalyptic number.

It is an amenable number.

129641729 is a deficient number, since it is larger than the sum of its proper divisors (18520255).

129641729 is an equidigital number, since it uses as much as digits as its factorization.

129641729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18520254.

The product of its digits is 54432, while the sum is 41.

The square root of 129641729 is about 11386.0321886072. The cubic root of 129641729 is about 506.1139075528.

The spelling of 129641729 in words is "one hundred twenty-nine million, six hundred forty-one thousand, seven hundred twenty-nine".