21000223231231 has 2 divisors, whose sum is σ = 21000223231232. Its totient is φ = 21000223231230.

The previous prime is 21000223231223. The next prime is 21000223231237. The reversal of 21000223231231 is 13213232200012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21000223231231 - 2³ = 21000223231223 is a prime.

It is a super-2 number, since 2×21000223231231² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000223231237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500111615615 + 10500111615616.

It is an arithmetic number, because the mean of its divisors is an integer number (10500111615616).

Almost surely, 2^{21000223231231} is an apocalyptic number.

21000223231231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000223231231 is an equidigital number, since it uses as much as digits as its factorization.

21000223231231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 22.

Adding to 21000223231231 its reverse (13213232200012), we get a palindrome (34213455431243).

The spelling of 21000223231231 in words is "twenty-one trillion, two hundred twenty-three million, two hundred thirty-one thousand, two hundred thirty-one".