66444672 has 128 divisors (see below), whose sum is σ = 212486400. Its totient is φ = 17971200.

The previous prime is 66444671. The next prime is 66444731. The reversal of 66444672 is 27644466.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a nude number because it is divisible by every one of its digits.

Its product of digits (193536) is a multiple of the sum of its prime factors (1344).

It is a self number, because there is not a number n which added to its sum of digits gives 66444672.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66444671) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50422 + ... + 51722.

It is an arithmetic number, because the mean of its divisors is an integer number (1660050).

Almost surely, 2^66444672 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 66444672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106243200).

66444672 is an abundant number, since it is smaller than the sum of its proper divisors (146041728).

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

66444672 is a wasteful number, since it uses less digits than its factorization.

66444672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1344 (or 1332 counting only the distinct ones).

The product of its digits is 193536, while the sum is 39.

The square root of 66444672 is about 8151.3601319044. The cubic root of 66444672 is about 405.0295604091.

The spelling of 66444672 in words is "sixty-six million, four hundred forty-four thousand, six hundred seventy-two".