66666684 has 48 divisors (see below), whose sum is σ = 181922048. Its totient is φ = 18603648.

The previous prime is 66666683. The next prime is 66666713. The reversal of 66666684 is 48666666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66666683) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5617 + ... + 12840.

Almost surely, 2^66666684 is an apocalyptic number.

It is an amenable number.

66666684 is an abundant number, since it is smaller than the sum of its proper divisors (115255364).

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

66666684 is a wasteful number, since it uses less digits than its factorization.

66666684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18514 (or 18512 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 48.

The square root of 66666684 is about 8164.9668707227. The cubic root of 66666684 is about 405.4801681798.

It can be divided in two parts, 6666 and 6684, that multiplied together give a palindrome (44555544).

The spelling of 66666684 in words is "sixty-six million, six hundred sixty-six thousand, six hundred eighty-four".