16504502681 has 2 divisors, whose sum is σ = 16504502682. Its totient is φ = 16504502680.

The previous prime is 16504502639. The next prime is 16504502701. The reversal of 16504502681 is 18620540561.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15448252681 + 1056250000 = 124291^2 + 32500^2 .

It is a cyclic number.

It is not a de Polignac number, because 16504502681 - 2¹⁸ = 16504240537 is a prime.

It is a super-3 number, since 3×16504502681³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (16504522681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8252251340 + 8252251341.

It is an arithmetic number, because the mean of its divisors is an integer number (8252251341).

Almost surely, 2^16504502681 is an apocalyptic number.

It is an amenable number.

16504502681 is a deficient number, since it is larger than the sum of its proper divisors (1).

16504502681 is an equidigital number, since it uses as much as digits as its factorization.

16504502681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 57600, while the sum is 38.

The spelling of 16504502681 in words is "sixteen billion, five hundred four million, five hundred two thousand, six hundred eighty-one".