66655386 has 96 divisors (see below), whose sum is σ = 174994560. Its totient is φ = 18983160.

The previous prime is 66655339. The next prime is 66655387. The reversal of 66655386 is 68355666.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66655387) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 214171 + ... + 214481.

It is an arithmetic number, because the mean of its divisors is an integer number (1822860).

Almost surely, 2^66655386 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66655386, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87497280).

66655386 is an abundant number, since it is smaller than the sum of its proper divisors (108339174).

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

66655386 is an equidigital number, since it uses as much as digits as its factorization.

66655386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348 (or 323 counting only the distinct ones).

The product of its digits is 777600, while the sum is 45.

The square root of 66655386 is about 8164.2749831201. The cubic root of 66655386 is about 405.4572613170.

The spelling of 66655386 in words is "sixty-six million, six hundred fifty-five thousand, three hundred eighty-six".