66878510169744 has 1920 divisors, whose sum is σ = 251620007288832. Its totient is φ = 16106278256640.

The previous prime is 66878510169743. The next prime is 66878510169749. The reversal of 66878510169744 is 44796101587866.

66878510169744 is a `hidden beast` number, since 6 + 6 + 8 + 7 + 8 + 510 + 1 + 69 + 7 + 44 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (66878510169743) by changing a digit.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 96785108439 + ... + 96785109129.

Almost surely, 2^{66878510169744} 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 66878510169744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125810003644416).

66878510169744 is an abundant number, since it is smaller than the sum of its proper divisors (184741497119088).

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

66878510169744 is a wasteful number, since it uses less digits than its factorization.

66878510169744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 957 (or 948 counting only the distinct ones).

The product of its (nonzero) digits is 487710720, while the sum is 72.

The spelling of 66878510169744 in words is "sixty-six trillion, eight hundred seventy-eight billion, five hundred ten million, one hundred sixty-nine thousand, seven hundred forty-four".