43638769 has 4 divisors (see below), whose sum is σ = 44462196. Its totient is φ = 42815344.

The previous prime is 43638761. The next prime is 43638781. The reversal of 43638769 is 96783634.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 96783634 = 2 ⋅48391817.

It can be written as a sum of positive squares in 2 ways, for example, as 20358144 + 23280625 = 4512^2 + 4825^2 .

It is a cyclic number.

It is not a de Polignac number, because 43638769 - 2³ = 43638761 is a prime.

It is a super-2 number, since 2×43638769² = 3808684319670722, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43638761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 411634 + ... + 411739.

It is an arithmetic number, because the mean of its divisors is an integer number (11115549).

Almost surely, 2^43638769 is an apocalyptic number.

It is an amenable number.

43638769 is a deficient number, since it is larger than the sum of its proper divisors (823427).

43638769 is an equidigital number, since it uses as much as digits as its factorization.

43638769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 823426.

The product of its digits is 653184, while the sum is 46.

The square root of 43638769 is about 6605.9646532509. The cubic root of 43638769 is about 352.0660629493.

The spelling of 43638769 in words is "forty-three million, six hundred thirty-eight thousand, seven hundred sixty-nine".