66790687 has 4 divisors (see below), whose sum is σ = 66879216. Its totient is φ = 66702160.

The previous prime is 66790679. The next prime is 66790699. The reversal of 66790687 is 78609766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78609766 = 2 ⋅39304883.

It is a cyclic number.

It is not a de Polignac number, because 66790687 - 2³ = 66790679 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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 66790687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66790627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43123 + ... + 44644.

It is an arithmetic number, because the mean of its divisors is an integer number (16719804).

Almost surely, 2^66790687 is an apocalyptic number.

66790687 is a deficient number, since it is larger than the sum of its proper divisors (88529).

66790687 is an equidigital number, since it uses as much as digits as its factorization.

66790687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88528.

The product of its (nonzero) digits is 762048, while the sum is 49.

The square root of 66790687 is about 8172.5569438212. The cubic root of 66790687 is about 405.7314161878.

The spelling of 66790687 in words is "sixty-six million, seven hundred ninety thousand, six hundred eighty-seven".