66788775 has 36 divisors (see below), whose sum is σ = 120851640. Its totient is φ = 35256000.

The previous prime is 66788753. The next prime is 66788783. The reversal of 66788775 is 57788766.

It is not a de Polignac number, because 66788775 - 2⁹ = 66788263 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 21256 + ... + 24194.

It is an arithmetic number, because the mean of its divisors is an integer number (3356990).

Almost surely, 2^66788775 is an apocalyptic number.

66788775 is a deficient number, since it is larger than the sum of its proper divisors (54062865).

66788775 is a wasteful number, since it uses less digits than its factorization.

66788775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3056 (or 3048 counting only the distinct ones).

The product of its digits is 3951360, while the sum is 54.

The square root of 66788775 is about 8172.4399661301. The cubic root of 66788775 is about 405.7275445608.

Subtracting from 66788775 its reverse (57788766), we obtain a palindrome (9000009).

The spelling of 66788775 in words is "sixty-six million, seven hundred eighty-eight thousand, seven hundred seventy-five".