42010221221 has 2 divisors, whose sum is σ = 42010221222. Its totient is φ = 42010221220.

The previous prime is 42010221217. The next prime is 42010221233. The reversal of 42010221221 is 12212201024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33056330596 + 8953890625 = 181814^2 + 94625^2 .

It is a cyclic number.

It is not a de Polignac number, because 42010221221 - 2² = 42010221217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42010221221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42010121221) 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, 21005110610 + 21005110611.

It is an arithmetic number, because the mean of its divisors is an integer number (21005110611).

Almost surely, 2^42010221221 is an apocalyptic number.

It is an amenable number.

42010221221 is a deficient number, since it is larger than the sum of its proper divisors (1).

42010221221 is an equidigital number, since it uses as much as digits as its factorization.

42010221221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 42010221221 its reverse (12212201024), we get a palindrome (54222422245).

The spelling of 42010221221 in words is "forty-two billion, ten million, two hundred twenty-one thousand, two hundred twenty-one".