66414240 has 144 divisors (see below), whose sum is σ = 240058728. Its totient is φ = 16662528.

The previous prime is 66414239. The next prime is 66414277. The reversal of 66414240 is 4241466.

66414240 is a `hidden beast` number, since 6 + 6 + 414 + 240 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 66389904 + 24336 = 8148^2 + 156^2 .

It is a tau number, because it is divible by the number of its divisors (144).

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, 23124 + ... + 25836.

Almost surely, 2^66414240 is an apocalyptic number.

66414240 is a gapful number since it is divisible by the number (60) 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 66414240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120029364).

66414240 is an abundant number, since it is smaller than the sum of its proper divisors (173644488).

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

66414240 is a wasteful number, since it uses less digits than its factorization.

66414240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2751 (or 2740 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 66414240 is about 8149.4932357785. The cubic root of 66414240 is about 404.9677157622.

The spelling of 66414240 in words is "sixty-six million, four hundred fourteen thousand, two hundred forty".