128783 has 4 divisors (see below), whose sum is σ = 130320. Its totient is φ = 127248.

The previous prime is 128767. The next prime is 128813. The reversal of 128783 is 387821.

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 128783 - 2⁴ = 128767 is a prime.

It is a super-2 number, since 2×128783² = 33170122178, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128483) 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, 635 + ... + 812.

It is an arithmetic number, because the mean of its divisors is an integer number (32580).

2¹²⁸⁷⁸³ is an apocalyptic number.

128783 is a deficient number, since it is larger than the sum of its proper divisors (1537).

128783 is an equidigital number, since it uses as much as digits as its factorization.

128783 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1536.

The product of its digits is 2688, while the sum is 29.

The square root of 128783 is about 358.8634837929. The cubic root of 128783 is about 50.4993954769.

The spelling of 128783 in words is "one hundred twenty-eight thousand, seven hundred eighty-three".