128369729 has 8 divisors (see below), whose sum is σ = 135744000. Its totient is φ = 121197600.

The previous prime is 128369723. The next prime is 128369741. The reversal of 128369729 is 927963821.

It is a happy number.

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

It is not a de Polignac number, because 128369729 - 2⁴ = 128369713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128369723) 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, 49229 + ... + 51770.

It is an arithmetic number, because the mean of its divisors is an integer number (16968000).

Almost surely, 2^128369729 is an apocalyptic number.

It is an amenable number.

128369729 is a deficient number, since it is larger than the sum of its proper divisors (7374271).

128369729 is a wasteful number, since it uses less digits than its factorization.

128369729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101071.

The product of its digits is 326592, while the sum is 47.

The square root of 128369729 is about 11330.0365842304. The cubic root of 128369729 is about 504.4531924069.

The spelling of 128369729 in words is "one hundred twenty-eight million, three hundred sixty-nine thousand, seven hundred twenty-nine".