66747953664 has 400 divisors, whose sum is σ = 230609243040. Its totient is φ = 19061360640.

The previous prime is 66747953651. The next prime is 66747953677. The reversal of 66747953664 is 46635974766.

It is an interprime number because it is at equal distance from previous prime (66747953651) and next prime (66747953677).

It is a Harshad number since it is a multiple of its sum of digits (63).

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 39 ways as a sum of consecutive naturals, for example, 33190419 + ... + 33192429.

Almost surely, 2^66747953664 is an apocalyptic number.

66747953664 is a gapful number since it is divisible by the number (64) 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 66747953664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115304621520).

66747953664 is an abundant number, since it is smaller than the sum of its proper divisors (163861289376).

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

66747953664 is an frugal number, since it uses more digits than its factorization.

66747953664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2066 (or 2023 counting only the distinct ones).

The product of its digits is 137168640, while the sum is 63.

The spelling of 66747953664 in words is "sixty-six billion, seven hundred forty-seven million, nine hundred fifty-three thousand, six hundred sixty-four".