111521 has 2 divisors, whose sum is σ = 111522. Its totient is φ = 111520.

The previous prime is 111509. The next prime is 111533. The reversal of 111521 is 125111.

It is a balanced prime because it is at equal distance from previous prime (111509) and next prime (111533).

It can be written as a sum of positive squares in only one way, i.e., 93025 + 18496 = 305^2 + 136^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111521 is a prime.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 111521.

It is not a weakly prime, because it can be changed into another prime (111581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55760 + 55761.

It is an arithmetic number, because the mean of its divisors is an integer number (55761).

2¹¹¹⁵²¹ is an apocalyptic number.

It is an amenable number.

111521 is a deficient number, since it is larger than the sum of its proper divisors (1).

111521 is an equidigital number, since it uses as much as digits as its factorization.

111521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10, while the sum is 11.

The square root of 111521 is about 333.9476006801. The cubic root of 111521 is about 48.1340293397.

Adding to 111521 its reverse (125111), we get a palindrome (236632).

The spelling of 111521 in words is "one hundred eleven thousand, five hundred twenty-one".