67721328264161 has 32 divisors (see below), whose sum is σ = 79704216230016. Its totient is φ = 56726604288000.

The previous prime is 67721328264061. The next prime is 67721328264173. The reversal of 67721328264161 is 16146282312776.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67721328264161 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 67721328264097 and 67721328264106.

It is not an unprimeable number, because it can be changed into a prime (67721328264061) 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, 2084294126 + ... + 2084326616.

It is an arithmetic number, because the mean of its divisors is an integer number (2490756757188).

Almost surely, 2^{67721328264161} is an apocalyptic number.

It is an amenable number.

67721328264161 is a deficient number, since it is larger than the sum of its proper divisors (11982887965855).

67721328264161 is a wasteful number, since it uses less digits than its factorization.

67721328264161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58353.

The product of its digits is 8128512, while the sum is 56.

The spelling of 67721328264161 in words is "sixty-seven trillion, seven hundred twenty-one billion, three hundred twenty-eight million, two hundred sixty-four thousand, one hundred sixty-one".