66286638 has 96 divisors (see below), whose sum is σ = 169827840. Its totient is φ = 18458880.

The previous prime is 66286613. The next prime is 66286657. The reversal of 66286638 is 83668266.

66286638 is a `hidden beast` number, since 6 + 6 + 2 + 8 + 6 + 638 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 66286593 and 66286602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 157993 + ... + 158411.

It is an arithmetic number, because the mean of its divisors is an integer number (1769040).

Almost surely, 2^66286638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66286638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84913920).

66286638 is an abundant number, since it is smaller than the sum of its proper divisors (103541202).

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

66286638 is a wasteful number, since it uses less digits than its factorization.

66286638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502 (or 499 counting only the distinct ones).

The product of its digits is 497664, while the sum is 45.

The square root of 66286638 is about 8141.6606414171. The cubic root of 66286638 is about 404.7081940084.

The spelling of 66286638 in words is "sixty-six million, two hundred eighty-six thousand, six hundred thirty-eight".