43509906 has 48 divisors (see below), whose sum is σ = 106293600. Its totient is φ = 13182840.

The previous prime is 43509901. The next prime is 43509911. The reversal of 43509906 is 60990534.

43509906 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (43509901) and next prime (43509911).

It is a super-2 number, since 2×43509906² = 3786223840257672, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (43509901) 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 in 23 ways as a sum of consecutive naturals, for example, 3205 + ... + 9863.

It is an arithmetic number, because the mean of its divisors is an integer number (2214450).

Almost surely, 2^43509906 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 43509906, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53146800).

43509906 is an abundant number, since it is smaller than the sum of its proper divisors (62783694).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

43509906 is a wasteful number, since it uses less digits than its factorization.

43509906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6692 (or 6675 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 36.

The square root of 43509906 is about 6596.2039083097. The cubic root of 43509906 is about 351.7191770628.

The spelling of 43509906 in words is "forty-three million, five hundred nine thousand, nine hundred six".