66666588 has 48 divisors (see below), whose sum is σ = 165745440. Its totient is φ = 20783104.

The previous prime is 66666569. The next prime is 66666629. The reversal of 66666588 is 88566666.

66666588 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a self number, because there is not a number n which added to its sum of digits gives 66666588.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34348 + ... + 36236.

It is an arithmetic number, because the mean of its divisors is an integer number (3453030).

Almost surely, 2^66666588 is an apocalyptic number.

66666588 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66666588, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82872720).

66666588 is an abundant number, since it is smaller than the sum of its proper divisors (99078852).

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

66666588 is a wasteful number, since it uses less digits than its factorization.

66666588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2086 (or 2084 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 51.

The square root of 66666588 is about 8164.9609919460. The cubic root of 66666588 is about 405.4799735493.

It can be divided in two parts, 6666658 and 8, that added together give a palindrome (6666666).

The spelling of 66666588 in words is "sixty-six million, six hundred sixty-six thousand, five hundred eighty-eight".