111712021 has 2 divisors, whose sum is σ = 111712022. Its totient is φ = 111712020.

The previous prime is 111711983. The next prime is 111712037. The reversal of 111712021 is 120217111.

It is an a-pointer prime, because the next prime (111712037) can be obtained adding 111712021 to its sum of digits (16).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 104346225 + 7365796 = 10215^2 + 2714^2 .

It is a cyclic number.

It is not a de Polignac number, because 111712021 - 2¹¹ = 111709973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111711986 and 111712004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111712421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55856010 + 55856011.

It is an arithmetic number, because the mean of its divisors is an integer number (55856011).

Almost surely, 2^111712021 is an apocalyptic number.

It is an amenable number.

111712021 is a deficient number, since it is larger than the sum of its proper divisors (1).

111712021 is an equidigital number, since it uses as much as digits as its factorization.

111712021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28, while the sum is 16.

The square root of 111712021 is about 10569.3907582225. The cubic root of 111712021 is about 481.6149611182.

Adding to 111712021 its reverse (120217111), we get a palindrome (231929132).

The spelling of 111712021 in words is "one hundred eleven million, seven hundred twelve thousand, twenty-one".