21220221999959 has 2 divisors, whose sum is σ = 21220221999960. Its totient is φ = 21220221999958.

The previous prime is 21220221999953. The next prime is 21220221999971. The reversal of 21220221999959 is 95999912202212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21220221999959 - 2⁴⁴ = 3628035955543 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220221999953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610110999979 + 10610110999980.

It is an arithmetic number, because the mean of its divisors is an integer number (10610110999980).

Almost surely, 2^{21220221999959} is an apocalyptic number.

21220221999959 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220221999959 is an equidigital number, since it uses as much as digits as its factorization.

21220221999959 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9447840, while the sum is 62.

The spelling of 21220221999959 in words is "twenty-one trillion, two hundred twenty billion, two hundred twenty-one million, nine hundred ninety-nine thousand, nine hundred fifty-nine".