21166552133 has 2 divisors, whose sum is σ = 21166552134. Its totient is φ = 21166552132.

The previous prime is 21166552061. The next prime is 21166552207. The reversal of 21166552133 is 33125566112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21124587649 + 41964484 = 145343^2 + 6478^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21166552133 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21166552093 and 21166552102.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21136552133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10583276066 + 10583276067.

It is an arithmetic number, because the mean of its divisors is an integer number (10583276067).

Almost surely, 2^21166552133 is an apocalyptic number.

It is an amenable number.

21166552133 is a deficient number, since it is larger than the sum of its proper divisors (1).

21166552133 is an equidigital number, since it uses as much as digits as its factorization.

21166552133 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32400, while the sum is 35.

The spelling of 21166552133 in words is "twenty-one billion, one hundred sixty-six million, five hundred fifty-two thousand, one hundred thirty-three".