111287881 has 2 divisors, whose sum is σ = 111287882. Its totient is φ = 111287880.

The previous prime is 111287873. The next prime is 111287887. The reversal of 111287881 is 188782111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 106915600 + 4372281 = 10340^2 + 2091^2 .

It is a cyclic number.

It is not a de Polignac number, because 111287881 - 2³ = 111287873 is a prime.

It is a super-2 number, since 2×111287881² = 24769984914940322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 111287881.

It is not a weakly prime, because it can be changed into another prime (111287887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55643940 + 55643941.

It is an arithmetic number, because the mean of its divisors is an integer number (55643941).

Almost surely, 2^111287881 is an apocalyptic number.

It is an amenable number.

111287881 is a deficient number, since it is larger than the sum of its proper divisors (1).

111287881 is an equidigital number, since it uses as much as digits as its factorization.

111287881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7168, while the sum is 37.

The square root of 111287881 is about 10549.3071336463. The cubic root of 111287881 is about 481.0046679843.

The spelling of 111287881 in words is "one hundred eleven million, two hundred eighty-seven thousand, eight hundred eighty-one".