66931948512 has 480 divisors, whose sum is σ = 232363676160. Its totient is φ = 18632954880.

The previous prime is 66931948507. The next prime is 66931948519. The reversal of 66931948512 is 21584913966.

66931948512 is a `hidden beast` number, since 6 + 6 + 9 + 31 + 94 + 8 + 512 = 666.

It is a super-2 number, since 2×66931948512² (a number of 22 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66931948519) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 133065253 + ... + 133065755.

It is an arithmetic number, because the mean of its divisors is an integer number (484090992).

Almost surely, 2^66931948512 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66931948512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116181838080).

66931948512 is an abundant number, since it is smaller than the sum of its proper divisors (165431727648).

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

66931948512 is a wasteful number, since it uses less digits than its factorization.

66931948512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908 (or 891 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The spelling of 66931948512 in words is "sixty-six billion, nine hundred thirty-one million, nine hundred forty-eight thousand, five hundred twelve".