66937609 has 4 divisors (see below), whose sum is σ = 66963204. Its totient is φ = 66912016.

The previous prime is 66937603. The next prime is 66937631. The reversal of 66937609 is 90673966.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15054400 + 51883209 = 3880^2 + 7203^2 .

It is a cyclic number.

It is not a de Polignac number, because 66937609 - 2⁹ = 66937097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66937603) 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, 8362 + ... + 14275.

It is an arithmetic number, because the mean of its divisors is an integer number (16740801).

Almost surely, 2^66937609 is an apocalyptic number.

It is an amenable number.

66937609 is a deficient number, since it is larger than the sum of its proper divisors (25595).

66937609 is a wasteful number, since it uses less digits than its factorization.

66937609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25594.

The product of its (nonzero) digits is 367416, while the sum is 46.

The square root of 66937609 is about 8181.5407473165. The cubic root of 66937609 is about 406.0286992258.

The spelling of 66937609 in words is "sixty-six million, nine hundred thirty-seven thousand, six hundred nine".