111541021 has 2 divisors, whose sum is σ = 111541022. Its totient is φ = 111541020.

The previous prime is 111541013. The next prime is 111541043. The reversal of 111541021 is 120145111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 95452900 + 16088121 = 9770^2 + 4011^2 .

It is a cyclic number.

It is not a de Polignac number, because 111541021 - 2³ = 111541013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111540986 and 111541004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111541321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55770510 + 55770511.

It is an arithmetic number, because the mean of its divisors is an integer number (55770511).

Almost surely, 2^111541021 is an apocalyptic number.

It is an amenable number.

111541021 is a deficient number, since it is larger than the sum of its proper divisors (1).

111541021 is an equidigital number, since it uses as much as digits as its factorization.

111541021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40, while the sum is 16.

The square root of 111541021 is about 10561.2982629978. The cubic root of 111541021 is about 481.3690961556.

Adding to 111541021 its reverse (120145111), we get a palindrome (231686132).

The spelling of 111541021 in words is "one hundred eleven million, five hundred forty-one thousand, twenty-one".