66666384 has 120 divisors (see below), whose sum is σ = 200123352. Its totient is φ = 20643840.

The previous prime is 66666371. The next prime is 66666409. The reversal of 66666384 is 48366666.

It can be written as a sum of positive squares in 4 ways, for example, as 7683984 + 58982400 = 2772^2 + 7680^2 .

It is a super-3 number, since 3×66666384³ (a number of 24 digits) contains 333 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 276504 + ... + 276744.

Almost surely, 2^66666384 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66666384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100061676).

66666384 is an abundant number, since it is smaller than the sum of its proper divisors (133456968).

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

66666384 is a wasteful number, since it uses less digits than its factorization.

66666384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385 (or 376 counting only the distinct ones).

The product of its digits is 746496, while the sum is 45.

The square root of 66666384 is about 8164.9484995314. The cubic root of 66666384 is about 405.4795599588.

The spelling of 66666384 in words is "sixty-six million, six hundred sixty-six thousand, three hundred eighty-four".