3930221 has 2 divisors, whose sum is σ = 3930222. Its totient is φ = 3930220.

The previous prime is 3930209. The next prime is 3930229. The reversal of 3930221 is 1220393.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3553225 + 376996 = 1885^2 + 614^2 .

It is an emirp because it is prime and its reverse (1220393) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3930221 - 2¹⁴ = 3913837 is a prime.

It is a Chen prime.

It is a nialpdrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 3930193 and 3930202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3930229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1965110 + 1965111.

It is an arithmetic number, because the mean of its divisors is an integer number (1965111).

Almost surely, 2^3930221 is an apocalyptic number.

It is an amenable number.

3930221 is a deficient number, since it is larger than the sum of its proper divisors (1).

3930221 is an equidigital number, since it uses as much as digits as its factorization.

3930221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 3930221 is about 1982.4784992529. The cubic root of 3930221 is about 157.8116245614.

The spelling of 3930221 in words is "three million, nine hundred thirty thousand, two hundred twenty-one".