111355212221 has 4 divisors (see below), whose sum is σ = 121478413344. Its totient is φ = 101232011100.

The previous prime is 111355212211. The next prime is 111355212277. The reversal of 111355212221 is 122212553111.

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, and also an emirpimes, since its reverse is a distinct semiprime: 122212553111 = 11 ⋅11110232101.

It is a de Polignac number, because none of the positive numbers 2^k-111355212221 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 (111355212211) 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, 5061600545 + ... + 5061600566.

It is an arithmetic number, because the mean of its divisors is an integer number (30369603336).

Almost surely, 2^111355212221 is an apocalyptic number.

111355212221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111355212221 is a deficient number, since it is larger than the sum of its proper divisors (10123201123).

111355212221 is a wasteful number, since it uses less digits than its factorization.

111355212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10123201122.

The product of its digits is 1200, while the sum is 26.

Adding to 111355212221 its reverse (122212553111), we get a palindrome (233567765332).

The spelling of 111355212221 in words is "one hundred eleven billion, three hundred fifty-five million, two hundred twelve thousand, two hundred twenty-one".