66564867 has 4 divisors (see below), whose sum is σ = 88753160. Its totient is φ = 44376576.

The previous prime is 66564851. The next prime is 66564871. The reversal of 66564867 is 76846566.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 66564867 - 2⁴ = 66564851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66564067) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11094142 + ... + 11094147.

It is an arithmetic number, because the mean of its divisors is an integer number (22188290).

Almost surely, 2^66564867 is an apocalyptic number.

66564867 is a deficient number, since it is larger than the sum of its proper divisors (22188293).

66564867 is a wasteful number, since it uses less digits than its factorization.

66564867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22188292.

The product of its digits is 1451520, while the sum is 48.

The square root of 66564867 is about 8158.7294966802. The cubic root of 66564867 is about 405.2736391856.

The spelling of 66564867 in words is "sixty-six million, five hundred sixty-four thousand, eight hundred sixty-seven".