129725705 has 8 divisors (see below), whose sum is σ = 156065352.
Its totient is φ = 103517568.
The previous prime is 129725693. The next prime is 129725707. The reversal of 129725705 is 507527921.
It can be written as a sum of positive squares in 4 ways, for example, as 45306361 + 84419344 = 6731^2 + 9188^2
It is a sphenic number, since it is the product of 3 distinct primes.
It is a cyclic number.
It is not a de Polignac number, because 129725705 - 212 = 129721609 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (129725707) 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, 30692 + ... + 34661.
It is an arithmetic number, because the mean of its divisors is an integer number (19508169).
Almost surely, 2129725705 is an apocalyptic number.
It is an amenable number.
129725705 is a deficient number, since it is larger than the sum of its proper divisors (26339647).
129725705 is an equidigital number, since it uses as much as digits as its factorization.
129725705 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 65755.
The product of its (nonzero) digits is 44100, while the sum is 38.
The square root of 129725705 is about 11389.7192678310.
The cubic root of 129725705 is about 506.2231631356.
The spelling of 129725705 in words is "one hundred twenty-nine million, seven hundred twenty-five thousand, seven hundred five".