66756801 has 4 divisors (see below), whose sum is σ = 89009072. Its totient is φ = 44504532.

The previous prime is 66756791. The next prime is 66756847. The reversal of 66756801 is 10865766.

66756801 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 66756801 - 2⁶ = 66756737 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66756801.

It is not an unprimeable number, because it can be changed into a prime (66751801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11126131 + ... + 11126136.

It is an arithmetic number, because the mean of its divisors is an integer number (22252268).

Almost surely, 2^66756801 is an apocalyptic number.

It is an amenable number.

66756801 is a deficient number, since it is larger than the sum of its proper divisors (22252271).

66756801 is a wasteful number, since it uses less digits than its factorization.

66756801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22252270.

The product of its (nonzero) digits is 60480, while the sum is 39.

The square root of 66756801 is about 8170.4835230236. The cubic root of 66756801 is about 405.6627891524.

The spelling of 66756801 in words is "sixty-six million, seven hundred fifty-six thousand, eight hundred one".