111231971 has 2 divisors, whose sum is σ = 111231972. Its totient is φ = 111231970.

The previous prime is 111231961. The next prime is 111231983. The reversal of 111231971 is 179132111.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 111231971 - 2¹⁸ = 110969827 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 111231971.

It is not a weakly prime, because it can be changed into another prime (111231961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55615985 + 55615986.

It is an arithmetic number, because the mean of its divisors is an integer number (55615986).

Almost surely, 2^111231971 is an apocalyptic number.

111231971 is a deficient number, since it is larger than the sum of its proper divisors (1).

111231971 is an equidigital number, since it uses as much as digits as its factorization.

111231971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 378, while the sum is 26.

The square root of 111231971 is about 10546.6568636701. The cubic root of 111231971 is about 480.9241037288.

The spelling of 111231971 in words is "one hundred eleven million, two hundred thirty-one thousand, nine hundred seventy-one".