128912287 has 6 divisors (see below), whose sum is σ = 149959248. Its totient is φ = 110496204.

The previous prime is 128912281. The next prime is 128912293. The reversal of 128912287 is 782219821.

It is an interprime number because it is at equal distance from previous prime (128912281) and next prime (128912293).

It is a de Polignac number, because none of the positive numbers 2^k-128912287 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 (128912281) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1315383 + ... + 1315480.

It is an arithmetic number, because the mean of its divisors is an integer number (24993208).

Almost surely, 2^128912287 is an apocalyptic number.

128912287 is a deficient number, since it is larger than the sum of its proper divisors (21046961).

128912287 is an equidigital number, since it uses as much as digits as its factorization.

128912287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2630877 (or 2630870 counting only the distinct ones).

The product of its digits is 32256, while the sum is 40.

The square root of 128912287 is about 11353.9546854829. The cubic root of 128912287 is about 505.1628883427.

The spelling of 128912287 in words is "one hundred twenty-eight million, nine hundred twelve thousand, two hundred eighty-seven".