221221010211997 has 2 divisors, whose sum is σ = 221221010211998. Its totient is φ = 221221010211996.

The previous prime is 221221010211967. The next prime is 221221010212003. The reversal of 221221010211997 is 799112010122122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 166421842410681 + 54799167801316 = 12900459^2 + 7402646^2 .

It is a cyclic number.

It is not a de Polignac number, because 221221010211997 - 2²⁷ = 221220875994269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221221010211907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110610505105998 + 110610505105999.

It is an arithmetic number, because the mean of its divisors is an integer number (110610505105999).

Almost surely, 2^{221221010211997} is an apocalyptic number.

It is an amenable number.

221221010211997 is a deficient number, since it is larger than the sum of its proper divisors (1).

221221010211997 is an equidigital number, since it uses as much as digits as its factorization.

221221010211997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 40.

The spelling of 221221010211997 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, ten million, two hundred eleven thousand, nine hundred ninety-seven".