21330010073 has 2 divisors, whose sum is σ = 21330010074. Its totient is φ = 21330010072.

The previous prime is 21330010069. The next prime is 21330010127. The reversal of 21330010073 is 37001003312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19066914889 + 2263095184 = 138083^2 + 47572^2 .

It is a cyclic number.

It is not a de Polignac number, because 21330010073 - 2² = 21330010069 is a prime.

It is not a weakly prime, because it can be changed into another prime (21330090073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10665005036 + 10665005037.

It is an arithmetic number, because the mean of its divisors is an integer number (10665005037).

Almost surely, 2^21330010073 is an apocalyptic number.

It is an amenable number.

21330010073 is a deficient number, since it is larger than the sum of its proper divisors (1).

21330010073 is an equidigital number, since it uses as much as digits as its factorization.

21330010073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 378, while the sum is 20.

Adding to 21330010073 its reverse (37001003312), we get a palindrome (58331013385).

The spelling of 21330010073 in words is "twenty-one billion, three hundred thirty million, ten thousand, seventy-three".