66385638 has 24 divisors (see below), whose sum is σ = 156911976. Its totient is φ = 20116800.

The previous prime is 66385633. The next prime is 66385643. The reversal of 66385638 is 83658366.

66385638 is a `hidden beast` number, since 6 + 6 + 3 + 8 + 5 + 638 = 666.

It is an interprime number because it is at equal distance from previous prime (66385633) and next prime (66385643).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 66385593 and 66385602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66385633) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 167443 + ... + 167838.

It is an arithmetic number, because the mean of its divisors is an integer number (6537999).

Almost surely, 2^66385638 is an apocalyptic number.

66385638 is an abundant number, since it is smaller than the sum of its proper divisors (90526338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66385638 is a wasteful number, since it uses less digits than its factorization.

66385638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335300 (or 335297 counting only the distinct ones).

The product of its digits is 622080, while the sum is 45.

The square root of 66385638 is about 8147.7382137621. The cubic root of 66385638 is about 404.9095728611.

The spelling of 66385638 in words is "sixty-six million, three hundred eighty-five thousand, six hundred thirty-eight".