11312321021 has 4 divisors (see below), whose sum is σ = 11343145152. Its totient is φ = 11281496892.

The previous prime is 11312321017. The next prime is 11312321057. The reversal of 11312321021 is 12012321311.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12012321311 = 94777 ⋅126743.

It is a cyclic number.

It is not a de Polignac number, because 11312321021 - 2² = 11312321017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11312324021) 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, 15411515 + ... + 15412248.

It is an arithmetic number, because the mean of its divisors is an integer number (2835786288).

Almost surely, 2^11312321021 is an apocalyptic number.

It is an amenable number.

11312321021 is a deficient number, since it is larger than the sum of its proper divisors (30824131).

11312321021 is an equidigital number, since it uses as much as digits as its factorization.

11312321021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30824130.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 11312321021 its reverse (12012321311), we get a palindrome (23324642332).

The spelling of 11312321021 in words is "eleven billion, three hundred twelve million, three hundred twenty-one thousand, twenty-one".