21166615334543 has 16 divisors (see below), whose sum is σ = 26727008624640. Its totient is φ = 16333171933056.

The previous prime is 21166615334461. The next prime is 21166615334561. The reversal of 21166615334543 is 34543351666112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21166615334543 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21166615334491 and 21166615334500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21166615334563) 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, 3866751983 + ... + 3866757456.

It is an arithmetic number, because the mean of its divisors is an integer number (1670438039040).

Almost surely, 2^{21166615334543} is an apocalyptic number.

21166615334543 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21166615334543 is a deficient number, since it is larger than the sum of its proper divisors (5560393290097).

21166615334543 is a wasteful number, since it uses less digits than its factorization.

21166615334543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7733509486.

The product of its digits is 4665600, while the sum is 50.

The spelling of 21166615334543 in words is "twenty-one trillion, one hundred sixty-six billion, six hundred fifteen million, three hundred thirty-four thousand, five hundred forty-three".