111091609 has 2 divisors, whose sum is σ = 111091610. Its totient is φ = 111091608.

The previous prime is 111091579. The next prime is 111091621. The reversal of 111091609 is 906190111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 111091600 + 9 = 10540^2 + 3^2 .

It is a cyclic number.

It is not a de Polignac number, because 111091609 - 2¹³ = 111083417 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (111091639) 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, 55545804 + 55545805.

It is an arithmetic number, because the mean of its divisors is an integer number (55545805).

Almost surely, 2^111091609 is an apocalyptic number.

It is an amenable number.

111091609 is a deficient number, since it is larger than the sum of its proper divisors (1).

111091609 is an equidigital number, since it uses as much as digits as its factorization.

111091609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 486, while the sum is 28.

The square root of 111091609 is about 10540.0004269450. Note that the first 3 decimals coincide. The cubic root of 111091609 is about 480.7217282120.

The spelling of 111091609 in words is "one hundred eleven million, ninety-one thousand, six hundred nine".