1100111221 has 16 divisors (see below), whose sum is σ = 1234066176. Its totient is φ = 972000000.

The previous prime is 1100111219. The next prime is 1100111231. The reversal of 1100111221 is 1221110011.

It is a 6-Lehmer number, since φ(1100111221) divides (1100111221-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 1100111221 - 2¹ = 1100111219 is a prime.

It is a super-2 number, since 2×1100111221² = 2420489397140221682, 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 = 1100111198 and 1100111207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1100111231) 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, 117721 + ... + 126721.

It is an arithmetic number, because the mean of its divisors is an integer number (77129136).

Almost surely, 2^1100111221 is an apocalyptic number.

1100111221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1100111221 is a deficient number, since it is larger than the sum of its proper divisors (133954955).

1100111221 is a wasteful number, since it uses less digits than its factorization.

1100111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9324.

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

The square root of 1100111221 is about 33167.9245808356. The cubic root of 1100111221 is about 1032.3149055647.

Adding to 1100111221 its reverse (1221110011), we get a palindrome (2321221232).

It can be divided in two parts, 110011 and 1221, that multiplied together give a palindrome (134323431).

The spelling of 1100111221 in words is "one billion, one hundred million, one hundred eleven thousand, two hundred twenty-one".