16721840667379 has 2 divisors, whose sum is σ = 16721840667380. Its totient is φ = 16721840667378.

The previous prime is 16721840667361. The next prime is 16721840667409. The reversal of 16721840667379 is 97376604812761.

It is a weak prime.

It is an emirp because it is prime and its reverse (97376604812761) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16721840667379 - 2¹¹ = 16721840665331 is a prime.

It is a super-2 number, since 2×16721840667379² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16721840667359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8360920333689 + 8360920333690.

It is an arithmetic number, because the mean of its divisors is an integer number (8360920333690).

Almost surely, 2^{16721840667379} is an apocalyptic number.

16721840667379 is a deficient number, since it is larger than the sum of its proper divisors (1).

16721840667379 is an equidigital number, since it uses as much as digits as its factorization.

16721840667379 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128024064, while the sum is 67.

The spelling of 16721840667379 in words is "sixteen trillion, seven hundred twenty-one billion, eight hundred forty million, six hundred sixty-seven thousand, three hundred seventy-nine".