20121331211323 has 4 divisors (see below), whose sum is σ = 20815170218640. Its totient is φ = 19427492204008.

The previous prime is 20121331211297. The next prime is 20121331211347. The reversal of 20121331211323 is 32311213312102.

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-20121331211323 is a prime.

It is a super-2 number, since 2×20121331211323² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20121331211383) 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, 346919503615 + ... + 346919503672.

It is an arithmetic number, because the mean of its divisors is an integer number (5203792554660).

Almost surely, 2^{20121331211323} is an apocalyptic number.

20121331211323 is a deficient number, since it is larger than the sum of its proper divisors (693839007317).

20121331211323 is an equidigital number, since it uses as much as digits as its factorization.

20121331211323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693839007316.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 20121331211323 its reverse (32311213312102), we get a palindrome (52432544523425).

The spelling of 20121331211323 in words is "twenty trillion, one hundred twenty-one billion, three hundred thirty-one million, two hundred eleven thousand, three hundred twenty-three".