23311001221 has 4 divisors (see below), whose sum is σ = 23693148844. Its totient is φ = 22928853600.

The previous prime is 23311001213. The next prime is 23311001227. The reversal of 23311001221 is 12210011332.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 420824196 + 22890177025 = 20514^2 + 151295^2 .

It is a cyclic number.

It is not a de Polignac number, because 23311001221 - 2³ = 23311001213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23311001195 and 23311001204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23311001227) 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, 191073720 + ... + 191073841.

It is an arithmetic number, because the mean of its divisors is an integer number (5923287211).

Almost surely, 2^23311001221 is an apocalyptic number.

It is an amenable number.

23311001221 is a deficient number, since it is larger than the sum of its proper divisors (382147623).

23311001221 is an equidigital number, since it uses as much as digits as its factorization.

23311001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382147622.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 23311001221 its reverse (12210011332), we get a palindrome (35521012553).

The spelling of 23311001221 in words is "twenty-three billion, three hundred eleven million, one thousand, two hundred twenty-one".