11211221222021 has 8 divisors (see below), whose sum is σ = 11314665625560. Its totient is φ = 11107787530752.

The previous prime is 11211221221987. The next prime is 11211221222101. The reversal of 11211221222021 is 12022212211211.

It can be written as a sum of positive squares in 4 ways, for example, as 4711118001121 + 6500103220900 = 2170511^2 + 2549530^2 .

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 11211221222021 - 2⁴² = 6813174710917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11211221221984 and 11211221222002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11211221222521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 567620 + ... + 4769133.

It is an arithmetic number, because the mean of its divisors is an integer number (1414333203195).

Almost surely, 2^{11211221222021} is an apocalyptic number.

It is an amenable number.

11211221222021 is a deficient number, since it is larger than the sum of its proper divisors (103444403539).

11211221222021 is a wasteful number, since it uses less digits than its factorization.

11211221222021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5356135.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 11211221222021 its reverse (12022212211211), we get a palindrome (23233433433232).

The spelling of 11211221222021 in words is "eleven trillion, two hundred eleven billion, two hundred twenty-one million, two hundred twenty-two thousand, twenty-one".