43989689 has 2 divisors, whose sum is σ = 43989690. Its totient is φ = 43989688.

The previous prime is 43989667. The next prime is 43989691. The reversal of 43989689 is 98698934.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27040000 + 16949689 = 5200^2 + 4117^2 .

It is a cyclic number.

It is not a de Polignac number, because 43989689 - 2¹² = 43985593 is a prime.

Together with 43989691, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (43989619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21994844 + 21994845.

It is an arithmetic number, because the mean of its divisors is an integer number (21994845).

Almost surely, 2^43989689 is an apocalyptic number.

It is an amenable number.

43989689 is a deficient number, since it is larger than the sum of its proper divisors (1).

43989689 is an equidigital number, since it uses as much as digits as its factorization.

43989689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3359232, while the sum is 56.

The square root of 43989689 is about 6632.4723143033. The cubic root of 43989689 is about 353.0072545436.

The spelling of 43989689 in words is "forty-three million, nine hundred eighty-nine thousand, six hundred eighty-nine".