21213124211023 has 4 divisors (see below), whose sum is σ = 21786451892440. Its totient is φ = 20639796529608.

The previous prime is 21213124211021. The next prime is 21213124211053. The reversal of 21213124211023 is 32011242131212.

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 21213124211023 - 2¹ = 21213124211021 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213124211021) 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, 286663840653 + ... + 286663840726.

It is an arithmetic number, because the mean of its divisors is an integer number (5446612973110).

Almost surely, 2^{21213124211023} is an apocalyptic number.

21213124211023 is a deficient number, since it is larger than the sum of its proper divisors (573327681417).

21213124211023 is an equidigital number, since it uses as much as digits as its factorization.

21213124211023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 573327681416.

The product of its (nonzero) digits is 1152, while the sum is 25.

Adding to 21213124211023 its reverse (32011242131212), we get a palindrome (53224366342235).

The spelling of 21213124211023 in words is "twenty-one trillion, two hundred thirteen billion, one hundred twenty-four million, two hundred eleven thousand, twenty-three".