549998221 has 2 divisors, whose sum is σ = 549998222. Its totient is φ = 549998220.

The previous prime is 549998203. The next prime is 549998261. The reversal of 549998221 is 122899945.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 348755625 + 201242596 = 18675^2 + 14186^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-549998221 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (549998201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 274999110 + 274999111.

It is an arithmetic number, because the mean of its divisors is an integer number (274999111).

Almost surely, 2^549998221 is an apocalyptic number.

It is an amenable number.

549998221 is a deficient number, since it is larger than the sum of its proper divisors (1).

549998221 is an equidigital number, since it uses as much as digits as its factorization.

549998221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 466560, while the sum is 49.

The square root of 549998221 is about 23452.0408706790. The cubic root of 549998221 is about 819.3203872224.

The spelling of 549998221 in words is "five hundred forty-nine million, nine hundred ninety-eight thousand, two hundred twenty-one".