66662928944640 has 1280 divisors, whose sum is σ = 275326835097600. Its totient is φ = 14974502731776.

The previous prime is 66662928944603. The next prime is 66662928944659. The reversal of 66662928944640 is 4644982926666.

It is a tau number, because it is divible by the number of its divisors (1280).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 6574896691 + ... + 6574906829.

It is an arithmetic number, because the mean of its divisors is an integer number (215099089920).

Almost surely, 2^{66662928944640} is an apocalyptic number.

66662928944640 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 66662928944640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137663417548800).

66662928944640 is an abundant number, since it is smaller than the sum of its proper divisors (208663906152960).

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

66662928944640 is a wasteful number, since it uses less digits than its factorization.

66662928944640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10412 (or 10390 counting only the distinct ones).

The product of its (nonzero) digits is 1289945088, while the sum is 72.

The spelling of 66662928944640 in words is "sixty-six trillion, six hundred sixty-two billion, nine hundred twenty-eight million, nine hundred forty-four thousand, six hundred forty".