43509109 has 6 divisors (see below), whose sum is σ = 50612694. Its totient is φ = 37293480.

The previous prime is 43509091. The next prime is 43509113. The reversal of 43509109 is 90190534.

It can be written as a sum of positive squares in only one way, i.e., 35070084 + 8439025 = 5922^2 + 2905^2 .

It is not a de Polignac number, because 43509109 - 2¹⁵ = 43476341 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 (43509119) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 443922 + ... + 444019.

It is an arithmetic number, because the mean of its divisors is an integer number (8435449).

Almost surely, 2^43509109 is an apocalyptic number.

43509109 is a gapful number since it is divisible by the number (49) formed by its first and last digit.

It is an amenable number.

43509109 is a deficient number, since it is larger than the sum of its proper divisors (7103585).

43509109 is an equidigital number, since it uses as much as digits as its factorization.

43509109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 887955 (or 887948 counting only the distinct ones).

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 43509109 is about 6596.1434944974. The cubic root of 43509109 is about 351.7170294914.

The spelling of 43509109 in words is "forty-three million, five hundred nine thousand, one hundred nine".