23121111513 has 4 divisors (see below), whose sum is σ = 30828148688. Its totient is φ = 15414074340.

The previous prime is 23121111499. The next prime is 23121111527. The reversal of 23121111513 is 31511112132.

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 an interprime number because it is at equal distance from previous prime (23121111499) and next prime (23121111527).

It is not a de Polignac number, because 23121111513 - 2¹³ = 23121103321 is a prime.

It is a super-2 number, since 2×23121111513² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 23121111513.

It is not an unprimeable number, because it can be changed into a prime (23121111553) 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, 3853518583 + ... + 3853518588.

It is an arithmetic number, because the mean of its divisors is an integer number (7707037172).

Almost surely, 2^23121111513 is an apocalyptic number.

It is an amenable number.

23121111513 is a deficient number, since it is larger than the sum of its proper divisors (7707037175).

23121111513 is an equidigital number, since it uses as much as digits as its factorization.

23121111513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7707037174.

The product of its digits is 180, while the sum is 21.

Adding to 23121111513 its reverse (31511112132), we get a palindrome (54632223645).

The spelling of 23121111513 in words is "twenty-three billion, one hundred twenty-one million, one hundred eleven thousand, five hundred thirteen".