21111244313 has 4 divisors (see below), whose sum is σ = 21111637008. Its totient is φ = 21110851620.

The previous prime is 21111244309. The next prime is 21111244421. The reversal of 21111244313 is 31344211112.

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 21111244313 - 2² = 21111244309 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21111244613) 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, 99923 + ... + 228488.

It is an arithmetic number, because the mean of its divisors is an integer number (5277909252).

Almost surely, 2^21111244313 is an apocalyptic number.

It is an amenable number.

21111244313 is a deficient number, since it is larger than the sum of its proper divisors (392695).

21111244313 is an equidigital number, since it uses as much as digits as its factorization.

21111244313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392694.

The product of its digits is 576, while the sum is 23.

Adding to 21111244313 its reverse (31344211112), we get a palindrome (52455455425).

The spelling of 21111244313 in words is "twenty-one billion, one hundred eleven million, two hundred forty-four thousand, three hundred thirteen".