67639646646 has 640 divisors, whose sum is σ = 197553033216. Its totient is φ = 16997713920.

The previous prime is 67639646629. The next prime is 67639646681. The reversal of 67639646646 is 64664693676.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 926570466 + ... + 926570538.

Almost surely, 2^67639646646 is an apocalyptic number.

67639646646 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 67639646646, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98776516608).

67639646646 is an abundant number, since it is smaller than the sum of its proper divisors (129913386570).

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

67639646646 is a wasteful number, since it uses less digits than its factorization.

67639646646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218 (or 209 counting only the distinct ones).

The product of its digits is 141087744, while the sum is 63.

The spelling of 67639646646 in words is "sixty-seven billion, six hundred thirty-nine million, six hundred forty-six thousand, six hundred forty-six".