21111102220997 has 2 divisors, whose sum is σ = 21111102220998. Its totient is φ = 21111102220996.

The previous prime is 21111102220963. The next prime is 21111102221017. The reversal of 21111102220997 is 79902220111112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12311579193796 + 8799523027201 = 3508786^2 + 2966399^2 .

It is a cyclic number.

It is not a de Polignac number, because 21111102220997 - 2¹² = 21111102216901 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21111102220997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111102220297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555551110498 + 10555551110499.

It is an arithmetic number, because the mean of its divisors is an integer number (10555551110499).

Almost surely, 2^{21111102220997} is an apocalyptic number.

It is an amenable number.

21111102220997 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111102220997 is an equidigital number, since it uses as much as digits as its factorization.

21111102220997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 38.

The spelling of 21111102220997 in words is "twenty-one trillion, one hundred eleven billion, one hundred two million, two hundred twenty thousand, nine hundred ninety-seven".