129640873 has 4 divisors (see below), whose sum is σ = 130924548. Its totient is φ = 128357200.

The previous prime is 129640813. The next prime is 129640891. The reversal of 129640873 is 378046921.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 115713049 + 13927824 = 10757^2 + 3732^2 .

It is a cyclic number.

It is not a de Polignac number, because 129640873 - 2¹⁷ = 129509801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129640813) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 641686 + ... + 641887.

It is an arithmetic number, because the mean of its divisors is an integer number (32731137).

Almost surely, 2^129640873 is an apocalyptic number.

It is an amenable number.

129640873 is a deficient number, since it is larger than the sum of its proper divisors (1283675).

129640873 is a wasteful number, since it uses less digits than its factorization.

129640873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1283674.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 129640873 is about 11385.9945986286. The cubic root of 129640873 is about 506.1127936253.

The spelling of 129640873 in words is "one hundred twenty-nine million, six hundred forty thousand, eight hundred seventy-three".