16721456516 has 12 divisors (see below), whose sum is σ = 29266970460. Its totient is φ = 8359464960.

The previous prime is 16721456497. The next prime is 16721456519. The reversal of 16721456516 is 61565412761.

It is a happy number.

16721456516 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 14088740416 + 2632716100 = 118696^2 + 51310^2 .

It is not an unprimeable number, because it can be changed into a prime (16721456519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 285725 + ... + 339236.

It is an arithmetic number, because the mean of its divisors is an integer number (2438914205).

Almost surely, 2^16721456516 is an apocalyptic number.

It is an amenable number.

16721456516 is a deficient number, since it is larger than the sum of its proper divisors (12545513944).

16721456516 is a wasteful number, since it uses less digits than its factorization.

16721456516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 631654 (or 631652 counting only the distinct ones).

The product of its digits is 302400, while the sum is 44.

The spelling of 16721456516 in words is "sixteen billion, seven hundred twenty-one million, four hundred fifty-six thousand, five hundred sixteen".