221021221009987 has 2 divisors, whose sum is σ = 221021221009988. Its totient is φ = 221021221009986.

The previous prime is 221021221009969. The next prime is 221021221010039. The reversal of 221021221009987 is 789900122120122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221021221009987 - 2⁴⁷ = 80283732654659 is a prime.

It is not a weakly prime, because it can be changed into another prime (221021221009187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110510610504993 + 110510610504994.

It is an arithmetic number, because the mean of its divisors is an integer number (110510610504994).

Almost surely, 2^{221021221009987} is an apocalyptic number.

221021221009987 is a deficient number, since it is larger than the sum of its proper divisors (1).

221021221009987 is an equidigital number, since it uses as much as digits as its factorization.

221021221009987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 46.

The spelling of 221021221009987 in words is "two hundred twenty-one trillion, twenty-one billion, two hundred twenty-one million, nine thousand, nine hundred eighty-seven".