66647287 has 16 divisors (see below), whose sum is σ = 77647680. Its totient is φ = 56028672.

The previous prime is 66647281. The next prime is 66647309. The reversal of 66647287 is 78274666.

It is not a de Polignac number, because 66647287 - 2³ = 66647279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66647281) 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 15 ways as a sum of consecutive naturals, for example, 85833 + ... + 86605.

It is an arithmetic number, because the mean of its divisors is an integer number (4852980).

Almost surely, 2^66647287 is an apocalyptic number.

66647287 is a deficient number, since it is larger than the sum of its proper divisors (11000393).

66647287 is a wasteful number, since it uses less digits than its factorization.

66647287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1002.

The product of its digits is 677376, while the sum is 46.

The square root of 66647287 is about 8163.7789656507. The cubic root of 66647287 is about 405.4408388814.

The spelling of 66647287 in words is "sixty-six million, six hundred forty-seven thousand, two hundred eighty-seven".