221111120081 has 2 divisors, whose sum is σ = 221111120082. Its totient is φ = 221111120080.

The previous prime is 221111120071. The next prime is 221111120123. The reversal of 221111120081 is 180021111122.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 166940885056 + 54170235025 = 408584^2 + 232745^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221111120081 is a prime.

It is a super-2 number, since 2×221111120081² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (221111120071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110555560040 + 110555560041.

It is an arithmetic number, because the mean of its divisors is an integer number (110555560041).

Almost surely, 2^221111120081 is an apocalyptic number.

It is an amenable number.

221111120081 is a deficient number, since it is larger than the sum of its proper divisors (1).

221111120081 is an equidigital number, since it uses as much as digits as its factorization.

221111120081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 20.

The spelling of 221111120081 in words is "two hundred twenty-one billion, one hundred eleven million, one hundred twenty thousand, eighty-one".