21113214616523 has 4 divisors (see below), whose sum is σ = 21116499703800. Its totient is φ = 21109929529248.

The previous prime is 21113214616517. The next prime is 21113214616531. The reversal of 21113214616523 is 32561641231112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21113214616523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21113214615523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1642533998 + ... + 1642546851.

It is an arithmetic number, because the mean of its divisors is an integer number (5279124925950).

Almost surely, 2^{21113214616523} is an apocalyptic number.

21113214616523 is a deficient number, since it is larger than the sum of its proper divisors (3285087277).

21113214616523 is an equidigital number, since it uses as much as digits as its factorization.

21113214616523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3285087276.

The product of its digits is 51840, while the sum is 38.

Adding to 21113214616523 its reverse (32561641231112), we get a palindrome (53674855847635).

The spelling of 21113214616523 in words is "twenty-one trillion, one hundred thirteen billion, two hundred fourteen million, six hundred sixteen thousand, five hundred twenty-three".