128711667 has 16 divisors (see below), whose sum is σ = 196735232. Its totient is φ = 73323360.

The previous prime is 128711663. The next prime is 128711699. The reversal of 128711667 is 766117821.

It is not a de Polignac number, because 128711667 - 2² = 128711663 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128711663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2308 + ... + 16209.

It is an arithmetic number, because the mean of its divisors is an integer number (12295952).

Almost surely, 2^128711667 is an apocalyptic number.

128711667 is a deficient number, since it is larger than the sum of its proper divisors (68023565).

128711667 is a wasteful number, since it uses less digits than its factorization.

128711667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18858.

The product of its digits is 28224, while the sum is 39.

The square root of 128711667 is about 11345.1164383624. The cubic root of 128711667 is about 504.9006987053.

The spelling of 128711667 in words is "one hundred twenty-eight million, seven hundred eleven thousand, six hundred sixty-seven".