20231021213231 has 4 divisors (see below), whose sum is σ = 20231050993392. Its totient is φ = 20230991433072.

The previous prime is 20231021213209. The next prime is 20231021213257. The reversal of 20231021213231 is 13231212013202.

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-20231021213231 is a prime.

It is a super-2 number, since 2×20231021213231² (a number of 27 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 = 20231021213197 and 20231021213206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20231021213131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13846691 + ... + 15237876.

It is an arithmetic number, because the mean of its divisors is an integer number (5057762748348).

Almost surely, 2^{20231021213231} is an apocalyptic number.

20231021213231 is a deficient number, since it is larger than the sum of its proper divisors (29780161).

20231021213231 is an equidigital number, since it uses as much as digits as its factorization.

20231021213231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29780160.

The product of its (nonzero) digits is 864, while the sum is 23.

Adding to 20231021213231 its reverse (13231212013202), we get a palindrome (33462233226433).

The spelling of 20231021213231 in words is "twenty trillion, two hundred thirty-one billion, twenty-one million, two hundred thirteen thousand, two hundred thirty-one".