66756765 has 16 divisors (see below), whose sum is σ = 107811648. Its totient is φ = 35270016.

The previous prime is 66756761. The next prime is 66756791. The reversal of 66756765 is 56765766.

It is not a de Polignac number, because 66756765 - 2² = 66756761 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66756761) 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, 19192 + ... + 22401.

It is an arithmetic number, because the mean of its divisors is an integer number (6738228).

Almost surely, 2^66756765 is an apocalyptic number.

It is an amenable number.

66756765 is a deficient number, since it is larger than the sum of its proper divisors (41054883).

66756765 is a wasteful number, since it uses less digits than its factorization.

66756765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41708.

The product of its digits is 1587600, while the sum is 48.

The square root of 66756765 is about 8170.4813199713. The cubic root of 66756765 is about 405.6627162316.

Subtracting from 66756765 its reverse (56765766), we obtain a palindrome (9990999).

The spelling of 66756765 in words is "sixty-six million, seven hundred fifty-six thousand, seven hundred sixty-five".