66686589 has 18 divisors (see below), whose sum is σ = 97408350. Its totient is φ = 43961328.

The previous prime is 66686569. The next prime is 66686647. The reversal of 66686589 is 98568666.

It can be written as a sum of positive squares in only one way, i.e., 44756100 + 21930489 = 6690^2 + 4683^2 .

It is a de Polignac number, because none of the positive numbers 2^k-66686589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66686539) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 298932 + ... + 299154.

It is an arithmetic number, because the mean of its divisors is an integer number (5411575).

Almost surely, 2^66686589 is an apocalyptic number.

It is an amenable number.

66686589 is a deficient number, since it is larger than the sum of its proper divisors (30721761).

66686589 is a wasteful number, since it uses less digits than its factorization.

66686589 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 601 (or 375 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 54.

The square root of 66686589 is about 8166.1857069258. The cubic root of 66686589 is about 405.5205195674.

The spelling of 66686589 in words is "sixty-six million, six hundred eighty-six thousand, five hundred eighty-nine".