43509073 has 2 divisors, whose sum is σ = 43509074. Its totient is φ = 43509072.

The previous prime is 43509049. The next prime is 43509079. The reversal of 43509073 is 37090534.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28547649 + 14961424 = 5343^2 + 3868^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43509073 is a prime.

It is equal to p_2633539 and since 43509073 and 2633539 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (43509079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21754536 + 21754537.

It is an arithmetic number, because the mean of its divisors is an integer number (21754537).

Almost surely, 2^43509073 is an apocalyptic number.

It is an amenable number.

43509073 is a deficient number, since it is larger than the sum of its proper divisors (1).

43509073 is an equidigital number, since it uses as much as digits as its factorization.

43509073 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11340, while the sum is 31.

The square root of 43509073 is about 6596.1407656296. The cubic root of 43509073 is about 351.7169324863.

The spelling of 43509073 in words is "forty-three million, five hundred nine thousand, seventy-three".