129127765 has 8 divisors (see below), whose sum is σ = 166872888. Its totient is φ = 95355840.

The previous prime is 129127763. The next prime is 129127777. The reversal of 129127765 is 567721921.

It can be written as a sum of positive squares in 4 ways, for example, as 4626801 + 124500964 = 2151^2 + 11158^2 .

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

It is not a de Polignac number, because 129127765 - 2¹ = 129127763 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129127763) 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, 993226 + ... + 993355.

It is an arithmetic number, because the mean of its divisors is an integer number (20859111).

Almost surely, 2^129127765 is an apocalyptic number.

It is an amenable number.

129127765 is a deficient number, since it is larger than the sum of its proper divisors (37745123).

129127765 is a wasteful number, since it uses less digits than its factorization.

129127765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1986599.

The product of its digits is 52920, while the sum is 40.

The square root of 129127765 is about 11363.4398401188. The cubic root of 129127765 is about 505.4441930419. Note that the first 3 decimals are identical.

The spelling of 129127765 in words is "one hundred twenty-nine million, one hundred twenty-seven thousand, seven hundred sixty-five".