111220021 has 8 divisors (see below), whose sum is σ = 121660704. Its totient is φ = 100834320.

The previous prime is 111219991. The next prime is 111220037. The reversal of 111220021 is 120022111.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 111220021 - 2⁵ = 111219989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111220051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9451 + ... + 17656.

It is an arithmetic number, because the mean of its divisors is an integer number (15207588).

Almost surely, 2^111220021 is an apocalyptic number.

111220021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111220021 is a deficient number, since it is larger than the sum of its proper divisors (10440683).

111220021 is a wasteful number, since it uses less digits than its factorization.

111220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27491.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 111220021 is about 10546.0903182175. The cubic root of 111220021 is about 480.9068807164.

Adding to 111220021 its reverse (120022111), we get a palindrome (231242132).

The spelling of 111220021 in words is "one hundred eleven million, two hundred twenty thousand, twenty-one".