20321231243 has 4 divisors (see below), whose sum is σ = 20511149400. Its totient is φ = 20131313088.

The previous prime is 20321231207. The next prime is 20321231251. The reversal of 20321231243 is 34213212302.

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 20321231243 - 2⁶ = 20321231179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20321237243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94958918 + ... + 94959131.

It is an arithmetic number, because the mean of its divisors is an integer number (5127787350).

Almost surely, 2^20321231243 is an apocalyptic number.

20321231243 is a deficient number, since it is larger than the sum of its proper divisors (189918157).

20321231243 is a wasteful number, since it uses less digits than its factorization.

20321231243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189918156.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 20321231243 its reverse (34213212302), we get a palindrome (54534443545).

The spelling of 20321231243 in words is "twenty billion, three hundred twenty-one million, two hundred thirty-one thousand, two hundred forty-three".