221221011009997 has 2 divisors, whose sum is σ = 221221011009998. Its totient is φ = 221221011009996.

The previous prime is 221221011009989. The next prime is 221221011010037. The reversal of 221221011009997 is 799900110122122.

221221011009997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 187007238653481 + 34213772356516 = 13675059^2 + 5849254^2 .

It is a cyclic number.

It is not a de Polignac number, because 221221011009997 - 2³ = 221221011009989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221221011009917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110610505504998 + 110610505504999.

It is an arithmetic number, because the mean of its divisors is an integer number (110610505504999).

Almost surely, 2^{221221011009997} is an apocalyptic number.

It is an amenable number.

221221011009997 is a deficient number, since it is larger than the sum of its proper divisors (1).

221221011009997 is an equidigital number, since it uses as much as digits as its factorization.

221221011009997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81648, while the sum is 46.

The spelling of 221221011009997 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, eleven million, nine thousand, nine hundred ninety-seven".