66720184580 has 288 divisors, whose sum is σ = 179688468960. Its totient is φ = 20652441600.

The previous prime is 66720184579. The next prime is 66720184591. The reversal of 66720184580 is 8548102766.

It can be written as a sum of positive squares in 16 ways, for example, as 3187957444 + 63532227136 = 56462^2 + 252056^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 95178230 + ... + 95178930.

It is an arithmetic number, because the mean of its divisors is an integer number (623918295).

Almost surely, 2^66720184580 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 66720184580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89844234480).

66720184580 is an abundant number, since it is smaller than the sum of its proper divisors (112968284380).

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

66720184580 is a wasteful number, since it uses less digits than its factorization.

66720184580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 967 (or 958 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 47.

The spelling of 66720184580 in words is "sixty-six billion, seven hundred twenty million, one hundred eighty-four thousand, five hundred eighty".