21312121030223 has 4 divisors (see below), whose sum is σ = 21312130334688. Its totient is φ = 21312111725760.

The previous prime is 21312121030157. The next prime is 21312121030283. The reversal of 21312121030223 is 32203012121312.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21312121030223 - 2⁸ = 21312121029967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312121030283) 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, 1462943 + ... + 6690623.

It is an arithmetic number, because the mean of its divisors is an integer number (5328032583672).

Almost surely, 2^{21312121030223} is an apocalyptic number.

21312121030223 is a deficient number, since it is larger than the sum of its proper divisors (9304465).

21312121030223 is an equidigital number, since it uses as much as digits as its factorization.

21312121030223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9304464.

The product of its (nonzero) digits is 864, while the sum is 23.

Adding to 21312121030223 its reverse (32203012121312), we get a palindrome (53515133151535).

The spelling of 21312121030223 in words is "twenty-one trillion, three hundred twelve billion, one hundred twenty-one million, thirty thousand, two hundred twenty-three".