221205983 has 2 divisors, whose sum is σ = 221205984. Its totient is φ = 221205982.

The previous prime is 221205949. The next prime is 221205991. The reversal of 221205983 is 389502122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221205983 - 2⁸ = 221205727 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221205913) 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, 110602991 + 110602992.

It is an arithmetic number, because the mean of its divisors is an integer number (110602992).

Almost surely, 2^221205983 is an apocalyptic number.

221205983 is a deficient number, since it is larger than the sum of its proper divisors (1).

221205983 is an equidigital number, since it uses as much as digits as its factorization.

221205983 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 221205983 is about 14872.9950917762. The cubic root of 221205983 is about 604.7821386189.

The spelling of 221205983 in words is "two hundred twenty-one million, two hundred five thousand, nine hundred eighty-three".