20123212231 has 4 divisors (see below), whose sum is σ = 20194319272. Its totient is φ = 20052105192.

The previous prime is 20123212183. The next prime is 20123212243. The reversal of 20123212231 is 13221232102.

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-20123212231 is a prime.

It is a super-2 number, since 2×20123212231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20123212199 and 20123212208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20123216231) 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, 35553096 + ... + 35553661.

It is an arithmetic number, because the mean of its divisors is an integer number (5048579818).

Almost surely, 2^20123212231 is an apocalyptic number.

20123212231 is a deficient number, since it is larger than the sum of its proper divisors (71107041).

20123212231 is an equidigital number, since it uses as much as digits as its factorization.

20123212231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71107040.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 20123212231 its reverse (13221232102), we get a palindrome (33344444333).

The spelling of 20123212231 in words is "twenty billion, one hundred twenty-three million, two hundred twelve thousand, two hundred thirty-one".