11000000001221 has 32 divisors (see below), whose sum is σ = 13750644741120. Its totient is φ = 8548732368000.

The previous prime is 11000000001181. The next prime is 11000000001343. The reversal of 11000000001221 is 12210000000011.

It is a de Polignac number, because none of the positive numbers 2^k-11000000001221 is a prime.

11000000001221 is a modest number, since divided by 1221 gives 11 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 11000000001199 and 11000000001208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11000000001121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 47039630 + ... + 47272896.

It is an arithmetic number, because the mean of its divisors is an integer number (429707648160).

Almost surely, 2^{11000000001221} is an apocalyptic number.

11000000001221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11000000001221 is a deficient number, since it is larger than the sum of its proper divisors (2750644739899).

11000000001221 is a wasteful number, since it uses less digits than its factorization.

11000000001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234905.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 11000000001221 its reverse (12210000000011), we get a palindrome (23210000001232).

The spelling of 11000000001221 in words is "eleven trillion, one thousand, two hundred twenty-one".