43128769 has 4 divisors (see below), whose sum is σ = 43835860. Its totient is φ = 42421680.

The previous prime is 43128763. The next prime is 43128809. The reversal of 43128769 is 96782134.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11992369 + 31136400 = 3463^2 + 5580^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43128769 is a prime.

It is a super-2 number, since 2×43128769² = 3720181430910722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43128763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 353454 + ... + 353575.

It is an arithmetic number, because the mean of its divisors is an integer number (10958965).

Almost surely, 2^43128769 is an apocalyptic number.

It is an amenable number.

43128769 is a deficient number, since it is larger than the sum of its proper divisors (707091).

43128769 is an equidigital number, since it uses as much as digits as its factorization.

43128769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 707090.

The product of its digits is 72576, while the sum is 40.

The square root of 43128769 is about 6567.2497287677. The cubic root of 43128769 is about 350.6891699854.

The spelling of 43128769 in words is "forty-three million, one hundred twenty-eight thousand, seven hundred sixty-nine".