66316647 has 4 divisors (see below), whose sum is σ = 88422200. Its totient is φ = 44211096.

The previous prime is 66316637. The next prime is 66316651. The reversal of 66316647 is 74661366.

It is a happy number.

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

It is not a de Polignac number, because 66316647 - 2⁶ = 66316583 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 (66316637) 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, 11052772 + ... + 11052777.

It is an arithmetic number, because the mean of its divisors is an integer number (22105550).

Almost surely, 2^66316647 is an apocalyptic number.

66316647 is a deficient number, since it is larger than the sum of its proper divisors (22105553).

66316647 is a wasteful number, since it uses less digits than its factorization.

66316647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22105552.

The product of its digits is 108864, while the sum is 39.

The square root of 66316647 is about 8143.5033615760. The cubic root of 66316647 is about 404.7692573755.

The spelling of 66316647 in words is "sixty-six million, three hundred sixteen thousand, six hundred forty-seven".