1111001221 has 16 divisors (see below), whose sum is σ = 1287923328. Its totient is φ = 947161600.

The previous prime is 1111001189. The next prime is 1111001233. The reversal of 1111001221 is 1221001111.

It is not a de Polignac number, because 1111001221 - 2⁵ = 1111001189 is a prime.

It is a Duffinian number.

1111001221 is a modest number, since divided by 1221 gives 1111 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 1111001198 and 1111001207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1111001261) 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, 41976 + ... + 63118.

It is an arithmetic number, because the mean of its divisors is an integer number (80495208).

Almost surely, 2^1111001221 is an apocalyptic number.

1111001221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1111001221 is a deficient number, since it is larger than the sum of its proper divisors (176922107).

1111001221 is a wasteful number, since it uses less digits than its factorization.

1111001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21452.

The product of its (nonzero) digits is 4, while the sum is 10.

The square root of 1111001221 is about 33331.6849409087. The cubic root of 1111001221 is about 1035.7100221130.

Adding to 1111001221 its reverse (1221001111), we get a palindrome (2332002332).

The spelling of 1111001221 in words is "one billion, one hundred eleven million, one thousand, two hundred twenty-one".