43981989 has 16 divisors (see below), whose sum is σ = 60724992. Its totient is φ = 28297728.

The previous prime is 43981981. The next prime is 43981999. The reversal of 43981989 is 98918934.

It is a happy number.

It is not a de Polignac number, because 43981989 - 2³ = 43981981 is a prime.

It is a super-2 number, since 2×43981989² = 3868830712792242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43981981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8157 + ... + 12429.

It is an arithmetic number, because the mean of its divisors is an integer number (3795312).

Almost surely, 2^43981989 is an apocalyptic number.

It is an amenable number.

43981989 is a deficient number, since it is larger than the sum of its proper divisors (16743003).

43981989 is a wasteful number, since it uses less digits than its factorization.

43981989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4396.

The product of its digits is 559872, while the sum is 51.

The square root of 43981989 is about 6631.8918115422. The cubic root of 43981989 is about 352.9866564252.

It can be divided in two parts, 439 and 81989, that added together give a palindrome (82428).

The spelling of 43981989 in words is "forty-three million, nine hundred eighty-one thousand, nine hundred eighty-nine".