128436911 has 4 divisors (see below), whose sum is σ = 132865800. Its totient is φ = 124008024.

The previous prime is 128436901. The next prime is 128436949. The reversal of 128436911 is 119634821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 128436911 - 2¹⁴ = 128420527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128436901) 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, 2214401 + ... + 2214458.

It is an arithmetic number, because the mean of its divisors is an integer number (33216450).

Almost surely, 2^128436911 is an apocalyptic number.

128436911 is a deficient number, since it is larger than the sum of its proper divisors (4428889).

128436911 is an equidigital number, since it uses as much as digits as its factorization.

128436911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4428888.

The product of its digits is 10368, while the sum is 35.

The square root of 128436911 is about 11333.0009706167. Note that the first 3 decimals coincide. The cubic root of 128436911 is about 504.5411785291.

The spelling of 128436911 in words is "one hundred twenty-eight million, four hundred thirty-six thousand, nine hundred eleven".