20211223231 has 2 divisors, whose sum is σ = 20211223232. Its totient is φ = 20211223230.

The previous prime is 20211223223. The next prime is 20211223261. The reversal of 20211223231 is 13232211202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20211223231 - 2³ = 20211223223 is a prime.

It is a super-2 number, since 2×20211223231² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20211223199 and 20211223208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20211223261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105611615 + 10105611616.

It is an arithmetic number, because the mean of its divisors is an integer number (10105611616).

Almost surely, 2^20211223231 is an apocalyptic number.

20211223231 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211223231 is an equidigital number, since it uses as much as digits as its factorization.

20211223231 is an odious number, because the sum of its binary digits is odd.

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

Adding to 20211223231 its reverse (13232211202), we get a palindrome (33443434433).

The spelling of 20211223231 in words is "twenty billion, two hundred eleven million, two hundred twenty-three thousand, two hundred thirty-one".