66356741520 has 240 divisors, whose sum is σ = 235233872640. Its totient is φ = 16716865536.

The previous prime is 66356741489. The next prime is 66356741557. The reversal of 66356741520 is 2514765366.

66356741520 is a `hidden beast` number, since 6 + 6 + 3 + 56 + 74 + 1 + 520 = 666.

66356741520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (240).

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5013952 + ... + 5027168.

It is an arithmetic number, because the mean of its divisors is an integer number (980141136).

Almost surely, 2^66356741520 is an apocalyptic number.

66356741520 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 66356741520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117616936320).

66356741520 is an abundant number, since it is smaller than the sum of its proper divisors (168877131120).

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

66356741520 is a wasteful number, since it uses less digits than its factorization.

66356741520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13622 (or 13613 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 45.

The spelling of 66356741520 in words is "sixty-six billion, three hundred fifty-six million, seven hundred forty-one thousand, five hundred twenty".