66756144 has 320 divisors, whose sum is σ = 239984640. Its totient is φ = 15482880.

The previous prime is 66756133. The next prime is 66756149. The reversal of 66756144 is 44165766.

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

It is a Harshad number since it is a multiple of its sum of digits (39).

Its product of digits (120960) is a multiple of the sum of its prime factors (108).

It is not an unprimeable number, because it can be changed into a prime (66756149) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2153409 + ... + 2153439.

It is an arithmetic number, because the mean of its divisors is an integer number (749952).

Almost surely, 2^66756144 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 66756144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119992320).

66756144 is an abundant number, since it is smaller than the sum of its proper divisors (173228496).

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

66756144 is a wasteful number, since it uses less digits than its factorization.

66756144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108 (or 102 counting only the distinct ones).

The product of its digits is 120960, while the sum is 39.

The square root of 66756144 is about 8170.4433172258. The cubic root of 66756144 is about 405.6614583450.

The spelling of 66756144 in words is "sixty-six million, seven hundred fifty-six thousand, one hundred forty-four".