111621311605 has 16 divisors (see below), whose sum is σ = 140318380800. Its totient is φ = 85126466880.

The previous prime is 111621311573. The next prime is 111621311609. The reversal of 111621311605 is 506113126111.

It is not a de Polignac number, because 111621311605 - 2⁵ = 111621311573 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111621311609) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4860711 + ... + 4883620.

It is an arithmetic number, because the mean of its divisors is an integer number (8769898800).

Almost surely, 2^111621311605 is an apocalyptic number.

It is an amenable number.

111621311605 is a deficient number, since it is larger than the sum of its proper divisors (28697069195).

111621311605 is an equidigital number, since it uses as much as digits as its factorization.

111621311605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9744444.

The product of its (nonzero) digits is 1080, while the sum is 28.

Adding to 111621311605 its reverse (506113126111), we get a palindrome (617734437716).

The spelling of 111621311605 in words is "one hundred eleven billion, six hundred twenty-one million, three hundred eleven thousand, six hundred five".