66380359680 has 768 divisors, whose sum is σ = 258987456000. Its totient is φ = 16052649984.

The previous prime is 66380359621. The next prime is 66380359733. The reversal of 66380359680 is 8695308366.

It is a tau number, because it is divible by the number of its divisors (768).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 136304397 + ... + 136304883.

It is an arithmetic number, because the mean of its divisors is an integer number (337223250).

Almost surely, 2^66380359680 is an apocalyptic number.

66380359680 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 66380359680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129493728000).

66380359680 is an abundant number, since it is smaller than the sum of its proper divisors (192607096320).

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

66380359680 is a wasteful number, since it uses less digits than its factorization.

66380359680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569 (or 543 counting only the distinct ones).

The product of its (nonzero) digits is 5598720, while the sum is 54.

The spelling of 66380359680 in words is "sixty-six billion, three hundred eighty million, three hundred fifty-nine thousand, six hundred eighty".