21166134211242 has 12 divisors (see below), whose sum is σ = 45859957457730. Its totient is φ = 7055378070408.

The previous prime is 21166134211223. The next prime is 21166134211247. The reversal of 21166134211242 is 24211243166112.

21166134211242 is a `hidden beast` number, since 2 + 1 + 1 + 6 + 61 + 342 + 11 + 242 = 666.

It can be written as a sum of positive squares in only one way, i.e., 11257105335921 + 9909028875321 = 3355161^2 + 3147861^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21166134211197 and 21166134211206.

It is not an unprimeable number, because it can be changed into a prime (21166134211247) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 587948172517 + ... + 587948172552.

Almost surely, 2^{21166134211242} is an apocalyptic number.

21166134211242 is an abundant number, since it is smaller than the sum of its proper divisors (24693823246488).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21166134211242 is a wasteful number, since it uses less digits than its factorization.

21166134211242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1175896345077 (or 1175896345074 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

Adding to 21166134211242 its reverse (24211243166112), we get a palindrome (45377377377354).

The spelling of 21166134211242 in words is "twenty-one trillion, one hundred sixty-six billion, one hundred thirty-four million, two hundred eleven thousand, two hundred forty-two".