66361680 has 600 divisors, whose sum is σ = 307882080. Its totient is φ = 13063680.

The previous prime is 66361663. The next prime is 66361709. The reversal of 66361680 is 8616366.

66361680 is a `hidden beast` number, since 6 + 636 + 16 + 8 + 0 = 666.

66361680 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 (36).

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 119 ways as a sum of consecutive naturals, for example, 3492711 + ... + 3492729.

Almost surely, 2^66361680 is an apocalyptic number.

66361680 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 66361680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (153941040).

66361680 is an abundant number, since it is smaller than the sum of its proper divisors (241520400).

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

66361680 is a wasteful number, since it uses less digits than its factorization.

66361680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 66361680 is about 8146.2678571233. The cubic root of 66361680 is about 404.8608575513.

The spelling of 66361680 in words is "sixty-six million, three hundred sixty-one thousand, six hundred eighty".