20111002211221 has 4 divisors (see below), whose sum is σ = 20111323018444. Its totient is φ = 20110681404000.

The previous prime is 20111002211213. The next prime is 20111002211269. The reversal of 20111002211221 is 12211220011102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9587141808721 + 10523860402500 = 3096311^2 + 3244050^2 .

It is a cyclic number.

It is not a de Polignac number, because 20111002211221 - 2³ = 20111002211213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20111002211195 and 20111002211204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111002211291) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 160309560 + ... + 160434961.

It is an arithmetic number, because the mean of its divisors is an integer number (5027830754611).

Almost surely, 2^{20111002211221} is an apocalyptic number.

It is an amenable number.

20111002211221 is a deficient number, since it is larger than the sum of its proper divisors (320807223).

20111002211221 is an equidigital number, since it uses as much as digits as its factorization.

20111002211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320807222.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 20111002211221 its reverse (12211220011102), we get a palindrome (32322222222323).

The spelling of 20111002211221 in words is "twenty trillion, one hundred eleven billion, two million, two hundred eleven thousand, two hundred twenty-one".