66311239680 has 960 divisors, whose sum is σ = 278555397120. Its totient is φ = 14834368512.

The previous prime is 66311239661. The next prime is 66311239697. The reversal of 66311239680 is 8693211366.

66311239680 is a `hidden beast` number, since 6 + 631 + 1 + 2 + 3 + 9 + 6 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

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 79 ways as a sum of consecutive naturals, for example, 1410877417 + ... + 1410877463.

It is an arithmetic number, because the mean of its divisors is an integer number (290161872).

Almost surely, 2^66311239680 is an apocalyptic number.

66311239680 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 66311239680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139277698560).

66311239680 is an abundant number, since it is smaller than the sum of its proper divisors (212244157440).

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

66311239680 is an frugal number, since it uses more digits than its factorization.

66311239680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The spelling of 66311239680 in words is "sixty-six billion, three hundred eleven million, two hundred thirty-nine thousand, six hundred eighty".