9920331320021 has 2 divisors, whose sum is σ = 9920331320022. Its totient is φ = 9920331320020.

The previous prime is 9920331319993. The next prime is 9920331320027. The reversal of 9920331320021 is 1200231330299.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7213602214225 + 2706729105796 = 2685815^2 + 1645214^2 .

It is an emirp because it is prime and its reverse (1200231330299) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9920331320021 - 2²⁶ = 9920264211157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9920331320027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4960165660010 + 4960165660011.

It is an arithmetic number, because the mean of its divisors is an integer number (4960165660011).

Almost surely, 2^{9920331320021} is an apocalyptic number.

It is an amenable number.

9920331320021 is a deficient number, since it is larger than the sum of its proper divisors (1).

9920331320021 is an equidigital number, since it uses as much as digits as its factorization.

9920331320021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 35.

The spelling of 9920331320021 in words is "nine trillion, nine hundred twenty billion, three hundred thirty-one million, three hundred twenty thousand, twenty-one".