66355470720 has 1728 divisors, whose sum is σ = 307603623600. Its totient is φ = 13113999360.

The previous prime is 66355470641. The next prime is 66355470757. The reversal of 66355470720 is 2707455366.

66355470720 is a `hidden beast` number, since 6 + 6 + 3 + 554 + 70 + 7 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 990380127 + ... + 990380193.

Almost surely, 2^66355470720 is an apocalyptic number.

66355470720 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 66355470720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (153801811800).

66355470720 is an abundant number, since it is smaller than the sum of its proper divisors (241248152880).

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

66355470720 is a wasteful number, since it uses less digits than its factorization.

66355470720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 1058400, while the sum is 45.

The spelling of 66355470720 in words is "sixty-six billion, three hundred fifty-five million, four hundred seventy thousand, seven hundred twenty".