30639221 has 2 divisors, whose sum is σ = 30639222. Its totient is φ = 30639220.

The previous prime is 30639211. The next prime is 30639227. The reversal of 30639221 is 12293603.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25140196 + 5499025 = 5014^2 + 2345^2 .

It is a cyclic number.

It is not a de Polignac number, because 30639221 - 2¹⁰ = 30638197 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30639227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15319610 + 15319611.

It is an arithmetic number, because the mean of its divisors is an integer number (15319611).

Almost surely, 2^30639221 is an apocalyptic number.

It is an amenable number.

30639221 is a deficient number, since it is larger than the sum of its proper divisors (1).

30639221 is an equidigital number, since it uses as much as digits as its factorization.

30639221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 26.

The square root of 30639221 is about 5535.2706347567. The cubic root of 30639221 is about 312.9146572267.

The spelling of 30639221 in words is "thirty million, six hundred thirty-nine thousand, two hundred twenty-one".