16580420208481 has 4 divisors (see below), whose sum is σ = 17555739044292. Its totient is φ = 15605101372672.

The previous prime is 16580420208463. The next prime is 16580420208523. The reversal of 16580420208481 is 18480202408561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12458139692881 + 4122280515600 = 3529609^2 + 2030340^2 .

It is a cyclic number.

It is not a de Polignac number, because 16580420208481 - 2¹⁵ = 16580420175713 is a prime.

It is a super-2 number, since 2×16580420208481² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16580420208461) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 487659417880 + ... + 487659417913.

It is an arithmetic number, because the mean of its divisors is an integer number (4388934761073).

Almost surely, 2^{16580420208481} is an apocalyptic number.

It is an amenable number.

16580420208481 is a deficient number, since it is larger than the sum of its proper divisors (975318835811).

16580420208481 is an equidigital number, since it uses as much as digits as its factorization.

16580420208481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 975318835810.

The product of its (nonzero) digits is 983040, while the sum is 49.

The spelling of 16580420208481 in words is "sixteen trillion, five hundred eighty billion, four hundred twenty million, two hundred eight thousand, four hundred eighty-one".