66609696 has 24 divisors (see below), whose sum is σ = 174850704. Its totient is φ = 22203200.

The previous prime is 66609691. The next prime is 66609727. The reversal of 66609696 is 69690666.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (66609691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 346830 + ... + 347021.

It is an arithmetic number, because the mean of its divisors is an integer number (7285446).

Almost surely, 2^66609696 is an apocalyptic number.

It is an amenable number.

66609696 is an abundant number, since it is smaller than the sum of its proper divisors (108241008).

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

66609696 is a wasteful number, since it uses less digits than its factorization.

66609696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693864 (or 693856 counting only the distinct ones).

The product of its (nonzero) digits is 629856, while the sum is 48.

The square root of 66609696 is about 8161.4763370361. The cubic root of 66609696 is about 405.3645977539.

The spelling of 66609696 in words is "sixty-six million, six hundred nine thousand, six hundred ninety-six".