101111221 has 4 divisors (see below), whose sum is σ = 102768844.
Its totient is φ = 99453600.
The previous prime is 101111203. The next prime is 101111237. The reversal of 101111221 is 122111101.
It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122111101 = 7 ⋅17444443.
It can be written as a sum of positive squares in 2 ways, for example, as 10595025 + 90516196 = 3255^2 + 9514^2
It is a cyclic number.
It is not a de Polignac number, because 101111221 - 217 = 100980149 is a prime.
It is a super-2 number, since 2×1011112212 = 20446958024221682, which contains 22 as substring.
It is a Duffinian number.
It is a junction number, because it is equal to n+sod(n) for n = 101111198 and 101111207.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (101111321) 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, 828720 + ... + 828841.
It is an arithmetic number, because the mean of its divisors is an integer number (25692211).
Almost surely, 2101111221 is an apocalyptic number.
It is an amenable number.
101111221 is a deficient number, since it is larger than the sum of its proper divisors (1657623).
101111221 is an equidigital number, since it uses as much as digits as its factorization.
101111221 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 1657622.
The product of its (nonzero) digits is 4, while the sum is 10.
The square root of 101111221 is about 10055.4075501692.
The cubic root of 101111221 is about 465.8718310597.
Adding to 101111221 its reverse (122111101), we get a palindrome (223222322).
The spelling of 101111221 in words is "one hundred one million, one hundred eleven thousand, two hundred twenty-one".