21020020000073 has 2 divisors, whose sum is σ = 21020020000074. Its totient is φ = 21020020000072.

The previous prime is 21020020000043. The next prime is 21020020000153. The reversal of 21020020000073 is 37000002002012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14687006163769 + 6333013836304 = 3832363^2 + 2516548^2 .

It is a cyclic number.

It is not a de Polignac number, because 21020020000073 - 2⁸ = 21020019999817 is a prime.

It is not a weakly prime, because it can be changed into another prime (21020020000043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510010000036 + 10510010000037.

It is an arithmetic number, because the mean of its divisors is an integer number (10510010000037).

Almost surely, 2^{21020020000073} is an apocalyptic number.

It is an amenable number.

21020020000073 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020020000073 is an equidigital number, since it uses as much as digits as its factorization.

21020020000073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168, while the sum is 17.

Adding to 21020020000073 its reverse (37000002002012), we get a palindrome (58020022002085).

The spelling of 21020020000073 in words is "twenty-one trillion, twenty billion, twenty million, seventy-three", and thus it is an aban number and an uban number.