11311020221 has 8 divisors (see below), whose sum is σ = 11537376888. Its totient is φ = 11085984000.

The previous prime is 11311020187. The next prime is 11311020257. The reversal of 11311020221 is 12202011311.

It can be written as a sum of positive squares in 4 ways, for example, as 1704864100 + 9606156121 = 41290^2 + 98011^2 .

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 11311020221 - 2¹⁸ = 11310758077 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 11311020196 and 11311020205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11311020421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 312800 + ... + 347081.

It is an arithmetic number, because the mean of its divisors is an integer number (1442172111).

Almost surely, 2^11311020221 is an apocalyptic number.

It is an amenable number.

11311020221 is a deficient number, since it is larger than the sum of its proper divisors (226356667).

11311020221 is an equidigital number, since it uses as much as digits as its factorization.

11311020221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660223.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 11311020221 its reverse (12202011311), we get a palindrome (23513031532).

It can be divided in two parts, 113110 and 20221, that added together give a palindrome (133331).

The spelling of 11311020221 in words is "eleven billion, three hundred eleven million, twenty thousand, two hundred twenty-one".