111721447 has 2 divisors, whose sum is σ = 111721448. Its totient is φ = 111721446.

The previous prime is 111721429. The next prime is 111721451. The reversal of 111721447 is 744127111.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111721447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111721417) 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, 55860723 + 55860724.

It is an arithmetic number, because the mean of its divisors is an integer number (55860724).

Almost surely, 2^111721447 is an apocalyptic number.

111721447 is a deficient number, since it is larger than the sum of its proper divisors (1).

111721447 is an equidigital number, since it uses as much as digits as its factorization.

111721447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1568, while the sum is 28.

The square root of 111721447 is about 10569.8366590974. The cubic root of 111721447 is about 481.6285065865.

Adding to 111721447 its reverse (744127111), we get a palindrome (855848558).

The spelling of 111721447 in words is "one hundred eleven million, seven hundred twenty-one thousand, four hundred forty-seven".