43661543 has 16 divisors (see below), whose sum is σ = 46080384. Its totient is φ = 41333760.

The previous prime is 43661537. The next prime is 43661551. The reversal of 43661543 is 34516634.

It is a cyclic number.

It is not a de Polignac number, because 43661543 - 2²⁰ = 42612967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43661533) 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, 278021 + ... + 278177.

It is an arithmetic number, because the mean of its divisors is an integer number (2880024).

Almost surely, 2^43661543 is an apocalyptic number.

43661543 is a deficient number, since it is larger than the sum of its proper divisors (2418841).

43661543 is a wasteful number, since it uses less digits than its factorization.

43661543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362.

The product of its digits is 25920, while the sum is 32.

The square root of 43661543 is about 6607.6881736353. The cubic root of 43661543 is about 352.1272971707.

The spelling of 43661543 in words is "forty-three million, six hundred sixty-one thousand, five hundred forty-three".