212221564649 has 2 divisors, whose sum is σ = 212221564650. Its totient is φ = 212221564648.

The previous prime is 212221564603. The next prime is 212221564661. The reversal of 212221564649 is 946465122212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 150150825049 + 62070739600 = 387493^2 + 249140^2 .

It is a cyclic number.

It is not a de Polignac number, because 212221564649 - 2⁸ = 212221564393 is a prime.

It is not a weakly prime, because it can be changed into another prime (212221564549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106110782324 + 106110782325.

It is an arithmetic number, because the mean of its divisors is an integer number (106110782325).

Almost surely, 2^212221564649 is an apocalyptic number.

It is an amenable number.

212221564649 is a deficient number, since it is larger than the sum of its proper divisors (1).

212221564649 is an equidigital number, since it uses as much as digits as its factorization.

212221564649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 414720, while the sum is 44.

The spelling of 212221564649 in words is "two hundred twelve billion, two hundred twenty-one million, five hundred sixty-four thousand, six hundred forty-nine".