20111221011 has 8 divisors (see below), whose sum is σ = 30645670144. Its totient is φ = 11492126280.

The previous prime is 20111221003. The next prime is 20111221021. The reversal of 20111221011 is 11012211102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20111221011 - 2³ = 20111221003 is a prime.

It is a super-3 number, since 3×20111221011³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20111221021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 478838575 + ... + 478838616.

It is an arithmetic number, because the mean of its divisors is an integer number (3830708768).

Almost surely, 2^20111221011 is an apocalyptic number.

20111221011 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20111221011 is a deficient number, since it is larger than the sum of its proper divisors (10534449133).

20111221011 is an equidigital number, since it uses as much as digits as its factorization.

20111221011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 957677201.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 20111221011 its reverse (11012211102), we get a palindrome (31123432113).

Subtracting from 20111221011 its reverse (11012211102), we obtain a palindrome (9099009909).

The spelling of 20111221011 in words is "twenty billion, one hundred eleven million, two hundred twenty-one thousand, eleven".