21035533442173 has 2 divisors, whose sum is σ = 21035533442174. Its totient is φ = 21035533442172.

The previous prime is 21035533442137. The next prime is 21035533442219. The reversal of 21035533442173 is 37124433553012.

Together with previous prime (21035533442137) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12751883876484 + 8283649565689 = 3570978^2 + 2878133^2 .

It is a cyclic number.

It is not a de Polignac number, because 21035533442173 - 2³⁷ = 20898094488701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21035533442123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10517766721086 + 10517766721087.

It is an arithmetic number, because the mean of its divisors is an integer number (10517766721087).

Almost surely, 2^{21035533442173} is an apocalyptic number.

It is an amenable number.

21035533442173 is a deficient number, since it is larger than the sum of its proper divisors (1).

21035533442173 is an equidigital number, since it uses as much as digits as its factorization.

21035533442173 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 907200, while the sum is 43.

Adding to 21035533442173 its reverse (37124433553012), we get a palindrome (58159966995185).

The spelling of 21035533442173 in words is "twenty-one trillion, thirty-five billion, five hundred thirty-three million, four hundred forty-two thousand, one hundred seventy-three".