111555811 has 2 divisors, whose sum is σ = 111555812. Its totient is φ = 111555810.

The previous prime is 111555797. The next prime is 111555869. The reversal of 111555811 is 118555111.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 111555811 - 2¹³ = 111547619 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 111555811.

It is not a weakly prime, because it can be changed into another prime (111555881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55777905 + 55777906.

It is an arithmetic number, because the mean of its divisors is an integer number (55777906).

Almost surely, 2^111555811 is an apocalyptic number.

111555811 is a deficient number, since it is larger than the sum of its proper divisors (1).

111555811 is an equidigital number, since it uses as much as digits as its factorization.

111555811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1000, while the sum is 28.

The square root of 111555811 is about 10561.9984377958. The cubic root of 111555811 is about 481.3903712411.

The spelling of 111555811 in words is "one hundred eleven million, five hundred fifty-five thousand, eight hundred eleven".