66788787 has 16 divisors (see below), whose sum is σ = 98997248. Its totient is φ = 39774240.

The previous prime is 66788783. The next prime is 66788797. The reversal of 66788787 is 78788766.

It is not a de Polignac number, because 66788787 - 2² = 66788783 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66788783) 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, 26413 + ... + 28830.

It is an arithmetic number, because the mean of its divisors is an integer number (6187328).

Almost surely, 2^66788787 is an apocalyptic number.

66788787 is a deficient number, since it is larger than the sum of its proper divisors (32208461).

66788787 is a wasteful number, since it uses less digits than its factorization.

66788787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55290.

The product of its digits is 6322176, while the sum is 57.

The square root of 66788787 is about 8172.4407003049. The cubic root of 66788787 is about 405.7275688600.

The spelling of 66788787 in words is "sixty-six million, seven hundred eighty-eight thousand, seven hundred eighty-seven".