66849389568 has 264 divisors, whose sum is σ = 209822412800. Its totient is φ = 20376354816.

The previous prime is 66849389567. The next prime is 66849389569. The reversal of 66849389568 is 86598394866.

66849389568 is a `hidden beast` number, since 6 + 6 + 8 + 493 + 89 + 56 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (66849389567) and next prime (66849389569).

It is a super-2 number, since 2×66849389568² (a number of 22 digits) contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 66849389496 and 66849389505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66849389567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13056513 + ... + 13061631.

Almost surely, 2^66849389568 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 66849389568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104911206400).

66849389568 is an abundant number, since it is smaller than the sum of its proper divisors (142973023232).

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

66849389568 is a wasteful number, since it uses less digits than its factorization.

66849389568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5267 (or 5246 counting only the distinct ones).

The product of its digits is 537477120, while the sum is 72.

The spelling of 66849389568 in words is "sixty-six billion, eight hundred forty-nine million, three hundred eighty-nine thousand, five hundred sixty-eight".