66919680000 has 720 divisors, whose sum is σ = 249625516140. Its totient is φ = 17252352000.

The previous prime is 66919679987. The next prime is 66919680007. The reversal of 66919680000 is 8691966.

It can be written as a sum of positive squares in 10 ways, for example, as 1759970304 + 65159709696 = 41952^2 + 255264^2 .

It is a tau number, because it is divible by the number of its divisors (720).

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

It is not an unprimeable number, because it can be changed into a prime (66919680007) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 426239922 + ... + 426240078.

Almost surely, 2^66919680000 is an apocalyptic number.

66919680000 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 66919680000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124812758070).

66919680000 is an abundant number, since it is smaller than the sum of its proper divisors (182705836140).

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

66919680000 is a wasteful number, since it uses less digits than its factorization.

66919680000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The spelling of 66919680000 in words is "sixty-six billion, nine hundred nineteen million, six hundred eighty thousand".