43459981 has 2 divisors, whose sum is σ = 43459982. Its totient is φ = 43459980.

The previous prime is 43459967. The next prime is 43459991. The reversal of 43459981 is 18995434.

It is a happy number.

43459981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39175081 + 4284900 = 6259^2 + 2070^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43459981 is a prime.

It is a super-2 number, since 2×43459981² = 3777539897040722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43459921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21729990 + 21729991.

It is an arithmetic number, because the mean of its divisors is an integer number (21729991).

Almost surely, 2^43459981 is an apocalyptic number.

It is an amenable number.

43459981 is a deficient number, since it is larger than the sum of its proper divisors (1).

43459981 is an equidigital number, since it uses as much as digits as its factorization.

43459981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 155520, while the sum is 43.

The square root of 43459981 is about 6592.4184484907. The cubic root of 43459981 is about 351.5846000435.

The spelling of 43459981 in words is "forty-three million, four hundred fifty-nine thousand, nine hundred eighty-one".