111721087 has 4 divisors (see below), whose sum is σ = 111745080. Its totient is φ = 111697096.

The previous prime is 111721081. The next prime is 111721109. The reversal of 111721087 is 780127111.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 111721087 - 2²³ = 103332479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111721081) 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 in 3 ways as a sum of consecutive naturals, for example, 2512 + ... + 15157.

It is an arithmetic number, because the mean of its divisors is an integer number (27936270).

Almost surely, 2^111721087 is an apocalyptic number.

111721087 is a deficient number, since it is larger than the sum of its proper divisors (23993).

111721087 is an equidigital number, since it uses as much as digits as its factorization.

111721087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23992.

The product of its (nonzero) digits is 784, while the sum is 28.

The square root of 111721087 is about 10569.8196294923. The cubic root of 111721087 is about 481.6279892688.

Adding to 111721087 its reverse (780127111), we get a palindrome (891848198).

The spelling of 111721087 in words is "one hundred eleven million, seven hundred twenty-one thousand, eighty-seven".