111661471 has 2 divisors, whose sum is σ = 111661472. Its totient is φ = 111661470.

The previous prime is 111661469. The next prime is 111661493. The reversal of 111661471 is 174166111.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 111661471 - 2¹ = 111661469 is a prime.

It is a super-3 number, since 3×111661471³ (a number of 25 digits) contains 333 as substring.

Together with 111661469, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111661441) 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, 55830735 + 55830736.

It is an arithmetic number, because the mean of its divisors is an integer number (55830736).

Almost surely, 2^111661471 is an apocalyptic number.

111661471 is a deficient number, since it is larger than the sum of its proper divisors (1).

111661471 is an equidigital number, since it uses as much as digits as its factorization.

111661471 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1008, while the sum is 28.

The square root of 111661471 is about 10566.9991482918. Note that the first 3 decimals coincide. The cubic root of 111661471 is about 481.5423061220.

The spelling of 111661471 in words is "one hundred eleven million, six hundred sixty-one thousand, four hundred seventy-one".