66874608640 has 352 divisors, whose sum is σ = 197555871744. Its totient is φ = 21215969280.

The previous prime is 66874608587. The next prime is 66874608643. The reversal of 66874608640 is 4680647866.

It is not an unprimeable number, because it can be changed into a prime (66874608643) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25552612 + ... + 25555228.

It is an arithmetic number, because the mean of its divisors is an integer number (561238272).

Almost surely, 2^66874608640 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 66874608640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98777935872).

66874608640 is an abundant number, since it is smaller than the sum of its proper divisors (130681263104).

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

66874608640 is a wasteful number, since it uses less digits than its factorization.

66874608640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2703 (or 2685 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 55.

The spelling of 66874608640 in words is "sixty-six billion, eight hundred seventy-four million, six hundred eight thousand, six hundred forty".