6750221 has 2 divisors, whose sum is σ = 6750222. Its totient is φ = 6750220.

The previous prime is 6750217. The next prime is 6750223. The reversal of 6750221 is 1220576.

6750221 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6180196 + 570025 = 2486^2 + 755^2 .

It is a cyclic number.

It is not a de Polignac number, because 6750221 - 2² = 6750217 is a prime.

Together with 6750223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6750223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3375110 + 3375111.

It is an arithmetic number, because the mean of its divisors is an integer number (3375111).

Almost surely, 2^6750221 is an apocalyptic number.

It is an amenable number.

6750221 is a deficient number, since it is larger than the sum of its proper divisors (1).

6750221 is an equidigital number, since it uses as much as digits as its factorization.

6750221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 6750221 is about 2598.1187424750. The cubic root of 6750221 is about 188.9902199991.

Adding to 6750221 its reverse (1220576), we get a palindrome (7970797).

The spelling of 6750221 in words is "six million, seven hundred fifty thousand, two hundred twenty-one".