111689129 has 2 divisors, whose sum is σ = 111689130. Its totient is φ = 111689128.

The previous prime is 111689111. The next prime is 111689131. The reversal of 111689129 is 921986111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 111091600 + 597529 = 10540^2 + 773^2 .

It is a cyclic number.

It is not a de Polignac number, because 111689129 - 2¹⁶ = 111623593 is a prime.

Together with 111689131, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 111689092 and 111689101.

It is not a weakly prime, because it can be changed into another prime (111689029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55844564 + 55844565.

It is an arithmetic number, because the mean of its divisors is an integer number (55844565).

Almost surely, 2^111689129 is an apocalyptic number.

It is an amenable number.

111689129 is a deficient number, since it is larger than the sum of its proper divisors (1).

111689129 is an equidigital number, since it uses as much as digits as its factorization.

111689129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 38.

The square root of 111689129 is about 10568.3077642544. The cubic root of 111689129 is about 481.5820613975.

The spelling of 111689129 in words is "one hundred eleven million, six hundred eighty-nine thousand, one hundred twenty-nine".