21033424073 has 2 divisors, whose sum is σ = 21033424074. Its totient is φ = 21033424072.

The previous prime is 21033424057. The next prime is 21033424109. The reversal of 21033424073 is 37042433012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20201505424 + 831918649 = 142132^2 + 28843^2 .

It is a cyclic number.

It is not a de Polignac number, because 21033424073 - 2⁴ = 21033424057 is a prime.

It is not a weakly prime, because it can be changed into another prime (21033424043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516712036 + 10516712037.

It is an arithmetic number, because the mean of its divisors is an integer number (10516712037).

Almost surely, 2^21033424073 is an apocalyptic number.

It is an amenable number.

21033424073 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033424073 is an equidigital number, since it uses as much as digits as its factorization.

21033424073 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 29.

Adding to 21033424073 its reverse (37042433012), we get a palindrome (58075857085).

The spelling of 21033424073 in words is "twenty-one billion, thirty-three million, four hundred twenty-four thousand, seventy-three".