111428689 has 4 divisors (see below), whose sum is σ = 111872880. Its totient is φ = 110984500.

The previous prime is 111428687. The next prime is 111428699. The reversal of 111428689 is 986824111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 111428689 - 2¹ = 111428687 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (111428683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 221719 + ... + 222220.

It is an arithmetic number, because the mean of its divisors is an integer number (27968220).

Almost surely, 2^111428689 is an apocalyptic number.

It is an amenable number.

111428689 is a deficient number, since it is larger than the sum of its proper divisors (444191).

111428689 is an equidigital number, since it uses as much as digits as its factorization.

111428689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444190.

The product of its digits is 27648, while the sum is 40.

The square root of 111428689 is about 10555.9788271860. The cubic root of 111428689 is about 481.2074476572.

The spelling of 111428689 in words is "one hundred eleven million, four hundred twenty-eight thousand, six hundred eighty-nine".