129756265 has 4 divisors (see below), whose sum is σ = 155707524. Its totient is φ = 103805008.

The previous prime is 129756239. The next prime is 129756269. The reversal of 129756265 is 562657921.

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 31091776 + 98664489 = 5576^2 + 9933^2 .

It is a cyclic number.

It is not a de Polignac number, because 129756265 - 2⁵ = 129756233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129756269) 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, 12975622 + ... + 12975631.

It is an arithmetic number, because the mean of its divisors is an integer number (38926881).

Almost surely, 2^129756265 is an apocalyptic number.

It is an amenable number.

129756265 is a deficient number, since it is larger than the sum of its proper divisors (25951259).

129756265 is an equidigital number, since it uses as much as digits as its factorization.

129756265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25951258.

The product of its digits is 226800, while the sum is 43.

The square root of 129756265 is about 11391.0607495527. The cubic root of 129756265 is about 506.2629110155.

The spelling of 129756265 in words is "one hundred twenty-nine million, seven hundred fifty-six thousand, two hundred sixty-five".