129561745 has 8 divisors (see below), whose sum is σ = 155814120. Its totient is φ = 103422720.

The previous prime is 129561739. The next prime is 129561749. The reversal of 129561745 is 547165921.

It can be written as a sum of positive squares in 4 ways, for example, as 14814801 + 114746944 = 3849^2 + 10712^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 129561745 - 2¹³ = 129553553 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 129561698 and 129561707.

It is not an unprimeable number, because it can be changed into a prime (129561749) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25800 + ... + 30409.

It is an arithmetic number, because the mean of its divisors is an integer number (19476765).

Almost surely, 2^129561745 is an apocalyptic number.

It is an amenable number.

129561745 is a deficient number, since it is larger than the sum of its proper divisors (26252375).

129561745 is an equidigital number, since it uses as much as digits as its factorization.

129561745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56675.

The product of its digits is 75600, while the sum is 40.

The square root of 129561745 is about 11382.5192729905. The cubic root of 129561745 is about 506.0098018171.

The spelling of 129561745 in words is "one hundred twenty-nine million, five hundred sixty-one thousand, seven hundred forty-five".