111421605 has 16 divisors (see below), whose sum is σ = 187657920. Its totient is φ = 56297088.

The previous prime is 111421601. The next prime is 111421619. The reversal of 111421605 is 506124111.

It is not a de Polignac number, because 111421605 - 2² = 111421601 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111421601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 195192 + ... + 195761.

It is an arithmetic number, because the mean of its divisors is an integer number (11728620).

Almost surely, 2^111421605 is an apocalyptic number.

111421605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

111421605 is a deficient number, since it is larger than the sum of its proper divisors (76236315).

111421605 is a wasteful number, since it uses less digits than its factorization.

111421605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 390980.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 111421605 is about 10555.6432774133. The cubic root of 111421605 is about 481.1972499668.

Adding to 111421605 its reverse (506124111), we get a palindrome (617545716).

The spelling of 111421605 in words is "one hundred eleven million, four hundred twenty-one thousand, six hundred five".