1021011111181 has 2 divisors, whose sum is σ = 1021011111182. Its totient is φ = 1021011111180.

The previous prime is 1021011111149. The next prime is 1021011111223. The reversal of 1021011111181 is 1811111101201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1020999098025 + 12013156 = 1010445^2 + 3466^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021011111181 - 2⁵ = 1021011111149 is a prime.

It is a super-2 number, since 2×1021011111181² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021011111881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510505555590 + 510505555591.

It is an arithmetic number, because the mean of its divisors is an integer number (510505555591).

Almost surely, 2^{1021011111181} is an apocalyptic number.

It is an amenable number.

1021011111181 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021011111181 is an equidigital number, since it uses as much as digits as its factorization.

1021011111181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 19.

Adding to 1021011111181 its reverse (1811111101201), we get a palindrome (2832122212382).

The spelling of 1021011111181 in words is "one trillion, twenty-one billion, eleven million, one hundred eleven thousand, one hundred eighty-one".