16515651606561 has 16 divisors (see below), whose sum is σ = 25906904481600. Its totient is φ = 10362761792064.

The previous prime is 16515651606557. The next prime is 16515651606611. The reversal of 16515651606561 is 16560615651561.

16515651606561 is a `hidden beast` number, since 1 + 6 + 5 + 1 + 5 + 6 + 516 + 0 + 65 + 61 = 666.

It is not a de Polignac number, because 16515651606561 - 2² = 16515651606557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16515651606498 and 16515651606507.

It is not an unprimeable number, because it can be changed into a prime (16515651606521) 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 15 ways as a sum of consecutive naturals, for example, 17990905431 + ... + 17990906348.

It is an arithmetic number, because the mean of its divisors is an integer number (1619181530100).

Almost surely, 2^{16515651606561} is an apocalyptic number.

It is an amenable number.

16515651606561 is a deficient number, since it is larger than the sum of its proper divisors (9391252875039).

16515651606561 is a wasteful number, since it uses less digits than its factorization.

16515651606561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35981811805 (or 35981811799 counting only the distinct ones).

The product of its (nonzero) digits is 4860000, while the sum is 54.

The spelling of 16515651606561 in words is "sixteen trillion, five hundred fifteen billion, six hundred fifty-one million, six hundred six thousand, five hundred sixty-one".