11211011111221 has 4 divisors (see below), whose sum is σ = 11261284703872. Its totient is φ = 11160737518572.

The previous prime is 11211011111119. The next prime is 11211011111231. The reversal of 11211011111221 is 12211111011211.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11211011111221 - 2¹³ = 11211011103029 is a prime.

It is a super-2 number, since 2×11211011111221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11211011111195 and 11211011111204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11211011111231) 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, 25136795991 + ... + 25136796436.

It is an arithmetic number, because the mean of its divisors is an integer number (2815321175968).

Almost surely, 2^{11211011111221} is an apocalyptic number.

It is an amenable number.

11211011111221 is a deficient number, since it is larger than the sum of its proper divisors (50273592651).

11211011111221 is an equidigital number, since it uses as much as digits as its factorization.

11211011111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50273592650.

The product of its (nonzero) digits is 8, while the sum is 16.

Adding to 11211011111221 its reverse (12211111011211), we get a palindrome (23422122122432).

It can be divided in two parts, 1121101 and 1111221, that added together give a palindrome (2232322).

The spelling of 11211011111221 in words is "eleven trillion, two hundred eleven billion, eleven million, one hundred eleven thousand, two hundred twenty-one".