66648637 has 16 divisors (see below), whose sum is σ = 76838400. Its totient is φ = 57173040.

The previous prime is 66648611. The next prime is 66648649. The reversal of 66648637 is 73684666.

It is a cyclic number.

It is not a de Polignac number, because 66648637 - 2⁷ = 66648509 is a prime.

It is a Duffinian number.

Its product of digits (870912) is a multiple of the sum of its prime divisors (1296).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66648607) 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, 72064 + ... + 72982.

It is an arithmetic number, because the mean of its divisors is an integer number (4802400).

Almost surely, 2^66648637 is an apocalyptic number.

It is an amenable number.

66648637 is a deficient number, since it is larger than the sum of its proper divisors (10189763).

66648637 is a wasteful number, since it uses less digits than its factorization.

66648637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1296.

The product of its digits is 870912, while the sum is 46.

The square root of 66648637 is about 8163.8616475293. The cubic root of 66648637 is about 405.4435763843.

The spelling of 66648637 in words is "sixty-six million, six hundred forty-eight thousand, six hundred thirty-seven".