67678817435721 has 12 divisors (see below), whose sum is σ = 97789159683072. Its totient is φ = 45104964932376.

The previous prime is 67678817435587. The next prime is 67678817435729. The reversal of 67678817435721 is 12753471887676.

67678817435721 is a `hidden beast` number, since 6 + 7 + 6 + 7 + 8 + 8 + 1 + 7 + 43 + 572 + 1 = 666.

It is not a de Polignac number, because 67678817435721 - 2²⁶ = 67678750326857 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 67678817435721.

It is not an unprimeable number, because it can be changed into a prime (67678817435729) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1187194201 + ... + 1187251206.

It is an arithmetic number, because the mean of its divisors is an integer number (8149096640256).

Almost surely, 2^{67678817435721} is an apocalyptic number.

It is an amenable number.

67678817435721 is a deficient number, since it is larger than the sum of its proper divisors (30110342247351).

67678817435721 is a wasteful number, since it uses less digits than its factorization.

67678817435721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2374448580 (or 2374448577 counting only the distinct ones).

The product of its digits is 663828480, while the sum is 72.

The spelling of 67678817435721 in words is "sixty-seven trillion, six hundred seventy-eight billion, eight hundred seventeen million, four hundred thirty-five thousand, seven hundred twenty-one".