21115526316223 has 4 divisors (see below), whose sum is σ = 21119352291360. Its totient is φ = 21111700341088.

The previous prime is 21115526316211. The next prime is 21115526316307. The reversal of 21115526316223 is 32261362551112.

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

It is a cyclic number.

It is not a de Polignac number, because 21115526316223 - 2⁹ = 21115526315711 is a prime.

It is a super-2 number, since 2×21115526316223² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115526316323) 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, 1912979290 + ... + 1912990327.

It is an arithmetic number, because the mean of its divisors is an integer number (5279838072840).

Almost surely, 2^{21115526316223} is an apocalyptic number.

21115526316223 is a deficient number, since it is larger than the sum of its proper divisors (3825975137).

21115526316223 is an equidigital number, since it uses as much as digits as its factorization.

21115526316223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3825975136.

The product of its digits is 129600, while the sum is 40.

Adding to 21115526316223 its reverse (32261362551112), we get a palindrome (53376888867335).

The spelling of 21115526316223 in words is "twenty-one trillion, one hundred fifteen billion, five hundred twenty-six million, three hundred sixteen thousand, two hundred twenty-three".