43538009 has 2 divisors, whose sum is σ = 43538010. Its totient is φ = 43538008.

The previous prime is 43537939. The next prime is 43538017. The reversal of 43538009 is 90083534.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41886784 + 1651225 = 6472^2 + 1285^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43538009 is a prime.

It is not a weakly prime, because it can be changed into another prime (43538909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21769004 + 21769005.

It is an arithmetic number, because the mean of its divisors is an integer number (21769005).

Almost surely, 2^43538009 is an apocalyptic number.

It is an amenable number.

43538009 is a deficient number, since it is larger than the sum of its proper divisors (1).

43538009 is an equidigital number, since it uses as much as digits as its factorization.

43538009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 43538009 is about 6598.3338048329. Note that the first 3 decimals coincide. The cubic root of 43538009 is about 351.7948857738.

The spelling of 43538009 in words is "forty-three million, five hundred thirty-eight thousand, nine".