66436609 has 4 divisors (see below), whose sum is σ = 66502080. Its totient is φ = 66371140.

The previous prime is 66436607. The next prime is 66436633. The reversal of 66436609 is 90663466.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66436609 - 2¹ = 66436607 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (66436607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31189 + ... + 33250.

It is an arithmetic number, because the mean of its divisors is an integer number (16625520).

Almost surely, 2^66436609 is an apocalyptic number.

It is an amenable number.

66436609 is a deficient number, since it is larger than the sum of its proper divisors (65471).

66436609 is a wasteful number, since it uses less digits than its factorization.

66436609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65470.

The product of its (nonzero) digits is 139968, while the sum is 40.

The square root of 66436609 is about 8150.8655368617. The cubic root of 66436609 is about 405.0131764244.

It can be divided in two parts, 664 and 36609, that added together give a palindrome (37273).

The spelling of 66436609 in words is "sixty-six million, four hundred thirty-six thousand, six hundred nine".