111110002021981 has 2 divisors, whose sum is σ = 111110002021982. Its totient is φ = 111110002021980.

The previous prime is 111110002021973. The next prime is 111110002022029. The reversal of 111110002021981 is 189120200011111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67791345602500 + 43318656419481 = 8233550^2 + 6581691^2 .

It is a cyclic number.

It is not a de Polignac number, because 111110002021981 - 2³ = 111110002021973 is a prime.

It is a super-2 number, since 2×111110002021981² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111110002021961) 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, 55555001010990 + 55555001010991.

It is an arithmetic number, because the mean of its divisors is an integer number (55555001010991).

Almost surely, 2^{111110002021981} is an apocalyptic number.

It is an amenable number.

111110002021981 is a deficient number, since it is larger than the sum of its proper divisors (1).

111110002021981 is an equidigital number, since it uses as much as digits as its factorization.

111110002021981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 28.

The spelling of 111110002021981 in words is "one hundred eleven trillion, one hundred ten billion, two million, twenty-one thousand, nine hundred eighty-one".