43999989 has 32 divisors (see below), whose sum is σ = 69120000. Its totient is φ = 24615360.

The previous prime is 43999981. The next prime is 43999999. The reversal of 43999989 is 98999934.

It is not a de Polignac number, because 43999989 - 2³ = 43999981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43999981) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21012 + ... + 23010.

It is an arithmetic number, because the mean of its divisors is an integer number (2160000).

Almost surely, 2^43999989 is an apocalyptic number.

It is an amenable number.

43999989 is a deficient number, since it is larger than the sum of its proper divisors (25120011).

43999989 is a wasteful number, since it uses less digits than its factorization.

43999989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2065.

The product of its digits is 5668704, while the sum is 60.

The square root of 43999989 is about 6633.2487515546. The cubic root of 43999989 is about 353.0348041130.

Subtracting 43999989 from its reverse (98999934), we obtain a palindrome (54999945).

It can be divided in two parts, 4 and 3999989, that added together give a palindrome (3999993).

The spelling of 43999989 in words is "forty-three million, nine hundred ninety-nine thousand, nine hundred eighty-nine".