128784545 has 4 divisors (see below), whose sum is σ = 154541460. Its totient is φ = 103027632.

The previous prime is 128784529. The next prime is 128784547. The reversal of 128784545 is 545487821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 545487821 = 41 ⋅13304581.

It can be written as a sum of positive squares in 2 ways, for example, as 13608721 + 115175824 = 3689^2 + 10732^2 .

It is a cyclic number.

It is not a de Polignac number, because 128784545 - 2⁴ = 128784529 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 128784496 and 128784505.

It is not an unprimeable number, because it can be changed into a prime (128784547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12878450 + ... + 12878459.

It is an arithmetic number, because the mean of its divisors is an integer number (38635365).

Almost surely, 2^128784545 is an apocalyptic number.

It is an amenable number.

128784545 is a deficient number, since it is larger than the sum of its proper divisors (25756915).

128784545 is an equidigital number, since it uses as much as digits as its factorization.

128784545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25756914.

The product of its digits is 358400, while the sum is 44.

The square root of 128784545 is about 11348.3278503928. The cubic root of 128784545 is about 504.9959742188.

The spelling of 128784545 in words is "one hundred twenty-eight million, seven hundred eighty-four thousand, five hundred forty-five".