128728267 has 8 divisors (see below), whose sum is σ = 137625696. Its totient is φ = 119978112.

The previous prime is 128728241. The next prime is 128728277. The reversal of 128728267 is 762827821.

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

It is not a de Polignac number, because 128728267 - 2¹⁵ = 128695499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128728207) 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, 35008 + ... + 38509.

It is an arithmetic number, because the mean of its divisors is an integer number (17203212).

Almost surely, 2^128728267 is an apocalyptic number.

128728267 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

128728267 is a deficient number, since it is larger than the sum of its proper divisors (8897429).

128728267 is a wasteful number, since it uses less digits than its factorization.

128728267 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73637.

The product of its digits is 150528, while the sum is 43.

The square root of 128728267 is about 11345.8480070905. The cubic root of 128728267 is about 504.9224035269.

The spelling of 128728267 in words is "one hundred twenty-eight million, seven hundred twenty-eight thousand, two hundred sixty-seven".