66649600 has 120 divisors (see below), whose sum is σ = 170489088. Its totient is φ = 25804800.

The previous prime is 66649591. The next prime is 66649603. The reversal of 66649600 is 694666.

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 66649600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66649603) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 524737 + ... + 524863.

Almost surely, 2^66649600 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66649600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85244544).

66649600 is an abundant number, since it is smaller than the sum of its proper divisors (103839488).

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

66649600 is a wasteful number, since it uses less digits than its factorization.

66649600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196 (or 175 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 37.

The square root of 66649600 is about 8163.9206267577. The cubic root of 66649600 is about 405.4455291138.

The spelling of 66649600 in words is "sixty-six million, six hundred forty-nine thousand, six hundred".