16553633635561 has 16 divisors (see below), whose sum is σ = 19121114560320. Its totient is φ = 14163285038080.

The previous prime is 16553633635559. The next prime is 16553633635573.

16553633635561 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 16553633635561 - 2¹ = 16553633635559 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16553633635496 and 16553633635505.

It is not an unprimeable number, because it can be changed into a prime (16553633635501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10168305 + ... + 11683393.

It is an arithmetic number, because the mean of its divisors is an integer number (1195069660020).

Almost surely, 2^{16553633635561} is an apocalyptic number.

16553633635561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16553633635561 is a deficient number, since it is larger than the sum of its proper divisors (2567480924759).

16553633635561 is a wasteful number, since it uses less digits than its factorization.

16553633635561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1573544.

The product of its digits is 65610000, while the sum is 58.

The spelling of 16553633635561 in words is "sixteen trillion, five hundred fifty-three billion, six hundred thirty-three million, six hundred thirty-five thousand, five hundred sixty-one".