11211021121221 has 24 divisors (see below), whose sum is σ = 16361892307800. Its totient is φ = 7396456704000.

The previous prime is 11211021121219. The next prime is 11211021121241. The reversal of 11211021121221 is 12212112011211.

It is a happy number.

11211021121221 is a `hidden beast` number, since 1 + 1 + 211 + 0 + 211 + 21 + 221 = 666.

11211021121221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 5579351064225 + 5631670056996 = 2362065^2 + 2373114^2 .

It is not a de Polignac number, because 11211021121221 - 2¹ = 11211021121219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11211021121194 and 11211021121203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11211021121241) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1071696 + ... + 4854953.

It is an arithmetic number, because the mean of its divisors is an integer number (681745512825).

Almost surely, 2^{11211021121221} is an apocalyptic number.

It is an amenable number.

11211021121221 is a deficient number, since it is larger than the sum of its proper divisors (5150871186579).

11211021121221 is a wasteful number, since it uses less digits than its factorization.

11211021121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5928837 (or 5928834 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 11211021121221 its reverse (12212112011211), we get a palindrome (23423133132432).

The spelling of 11211021121221 in words is "eleven trillion, two hundred eleven billion, twenty-one million, one hundred twenty-one thousand, two hundred twenty-one".