43758661 has 2 divisors, whose sum is σ = 43758662. Its totient is φ = 43758660.

The previous prime is 43758607. The next prime is 43758677. The reversal of 43758661 is 16685734.

It is a happy number.

43758661 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., 31013761 + 12744900 = 5569^2 + 3570^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43758661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43758461) 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, 21879330 + 21879331.

It is an arithmetic number, because the mean of its divisors is an integer number (21879331).

Almost surely, 2^43758661 is an apocalyptic number.

It is an amenable number.

43758661 is a deficient number, since it is larger than the sum of its proper divisors (1).

43758661 is an equidigital number, since it uses as much as digits as its factorization.

43758661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120960, while the sum is 40.

The square root of 43758661 is about 6615.0329553223. The cubic root of 43758661 is about 352.3881871278.

The spelling of 43758661 in words is "forty-three million, seven hundred fifty-eight thousand, six hundred sixty-one".