66808755 has 24 divisors (see below), whose sum is σ = 124710768. Its totient is φ = 32890176.

The previous prime is 66808747. The next prime is 66808757. The reversal of 66808755 is 55780866.

It is not a de Polignac number, because 66808755 - 2³ = 66808747 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 66808755.

It is not an unprimeable number, because it can be changed into a prime (66808757) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 56517 + ... + 57686.

It is an arithmetic number, because the mean of its divisors is an integer number (5196282).

Almost surely, 2^66808755 is an apocalyptic number.

66808755 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

66808755 is a deficient number, since it is larger than the sum of its proper divisors (57902013).

66808755 is a wasteful number, since it uses less digits than its factorization.

66808755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114227 (or 114224 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 45.

The square root of 66808755 is about 8173.6622758712. The cubic root of 66808755 is about 405.7679986048.

The spelling of 66808755 in words is "sixty-six million, eight hundred eight thousand, seven hundred fifty-five".