21312011223 has 32 divisors (see below), whose sum is σ = 34509035520. Its totient is φ = 12940871040.

The previous prime is 21312011183. The next prime is 21312011233. The reversal of 21312011223 is 32211021312.

It is not a de Polignac number, because 21312011223 - 2⁶ = 21312011159 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21312011196 and 21312011205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312011233) 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 31 ways as a sum of consecutive naturals, for example, 734665 + ... + 763122.

It is an arithmetic number, because the mean of its divisors is an integer number (1078407360).

Almost surely, 2^21312011223 is an apocalyptic number.

21312011223 is a deficient number, since it is larger than the sum of its proper divisors (13197024297).

21312011223 is a wasteful number, since it uses less digits than its factorization.

21312011223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1497844 (or 1497838 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21312011223 its reverse (32211021312), we get a palindrome (53523032535).

The spelling of 21312011223 in words is "twenty-one billion, three hundred twelve million, eleven thousand, two hundred twenty-three".