11001111221221 has 8 divisors (see below), whose sum is σ = 12001352592384. Its totient is φ = 10000893241920.

The previous prime is 11001111221209. The next prime is 11001111221239. The reversal of 11001111221221 is 12212211110011.

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 11001111221221 - 2⁵ = 11001111221189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11001111221195 and 11001111221204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11001111221281) 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, 4857316 + ... + 6752461.

It is an arithmetic number, because the mean of its divisors is an integer number (1500169074048).

Almost surely, 2^{11001111221221} is an apocalyptic number.

11001111221221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11001111221221 is a deficient number, since it is larger than the sum of its proper divisors (1000241371163).

11001111221221 is a wasteful number, since it uses less digits than its factorization.

11001111221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11695931.

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 11001111221221 its reverse (12212211110011), we get a palindrome (23213322331232).

The spelling of 11001111221221 in words is "eleven trillion, one billion, one hundred eleven million, two hundred twenty-one thousand, two hundred twenty-one".