100221111 has 8 divisors (see below), whose sum is σ = 148475760. Its totient is φ = 66814056.

The previous prime is 100221101. The next prime is 100221131. The reversal of 100221111 is 111122001.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-100221111 is a prime.

It is a super-4 number, since 4×100221111⁴ (a number of 33 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 100221093 and 100221102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100221101) 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, 1855920 + ... + 1855973.

It is an arithmetic number, because the mean of its divisors is an integer number (18559470).

Almost surely, 2^100221111 is an apocalyptic number.

100221111 is a deficient number, since it is larger than the sum of its proper divisors (48254649).

100221111 is an equidigital number, since it uses as much as digits as its factorization.

100221111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3711902 (or 3711896 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 100221111 is about 10011.0494454877. The cubic root of 100221111 is about 464.5007336449.

Adding to 100221111 its reverse (111122001), we get a palindrome (211343112).

The spelling of 100221111 in words is "one hundred million, two hundred twenty-one thousand, one hundred eleven".