993420221 has 2 divisors, whose sum is σ = 993420222. Its totient is φ = 993420220.

The previous prime is 993420193. The next prime is 993420227. The reversal of 993420221 is 122024399.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 646939225 + 346480996 = 25435^2 + 18614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-993420221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (993420227) 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, 496710110 + 496710111.

It is an arithmetic number, because the mean of its divisors is an integer number (496710111).

Almost surely, 2^993420221 is an apocalyptic number.

It is an amenable number.

993420221 is a deficient number, since it is larger than the sum of its proper divisors (1).

993420221 is an equidigital number, since it uses as much as digits as its factorization.

993420221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 993420221 is about 31518.5694630959. The cubic root of 993420221 is about 997.8019122838.

The spelling of 993420221 in words is "nine hundred ninety-three million, four hundred twenty thousand, two hundred twenty-one".