21168158833 has 2 divisors, whose sum is σ = 21168158834. Its totient is φ = 21168158832.

The previous prime is 21168158801. The next prime is 21168158839. The reversal of 21168158833 is 33885186112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21157738849 + 10419984 = 145457^2 + 3228^2 .

It is a cyclic number.

It is not a de Polignac number, because 21168158833 - 2⁵ = 21168158801 is a prime.

It is not a weakly prime, because it can be changed into another prime (21168158839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10584079416 + 10584079417.

It is an arithmetic number, because the mean of its divisors is an integer number (10584079417).

Almost surely, 2^21168158833 is an apocalyptic number.

It is an amenable number.

21168158833 is a deficient number, since it is larger than the sum of its proper divisors (1).

21168158833 is an equidigital number, since it uses as much as digits as its factorization.

21168158833 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 276480, while the sum is 46.

The spelling of 21168158833 in words is "twenty-one billion, one hundred sixty-eight million, one hundred fifty-eight thousand, eight hundred thirty-three".