21033108973 has 2 divisors, whose sum is σ = 21033108974. Its totient is φ = 21033108972.

The previous prime is 21033108961. The next prime is 21033108983. The reversal of 21033108973 is 37980133012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20187578889 + 845530084 = 142083^2 + 29078^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033108973 is a prime.

It is a super-2 number, since 2×21033108973² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21033108953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516554486 + 10516554487.

It is an arithmetic number, because the mean of its divisors is an integer number (10516554487).

Almost surely, 2^21033108973 is an apocalyptic number.

It is an amenable number.

21033108973 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033108973 is an equidigital number, since it uses as much as digits as its factorization.

21033108973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 37.

The spelling of 21033108973 in words is "twenty-one billion, thirty-three million, one hundred eight thousand, nine hundred seventy-three".