81589421233 has 2 divisors, whose sum is σ = 81589421234. Its totient is φ = 81589421232.

The previous prime is 81589421231. The next prime is 81589421239. The reversal of 81589421233 is 33212498518.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51115783744 + 30473637489 = 226088^2 + 174567^2 .

It is a cyclic number.

It is not a de Polignac number, because 81589421233 - 2¹ = 81589421231 is a prime.

It is a super-2 number, since 2×81589421233² (a number of 23 digits) contains 22 as substring.

Together with 81589421231, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (81589421231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40794710616 + 40794710617.

It is an arithmetic number, because the mean of its divisors is an integer number (40794710617).

Almost surely, 2^81589421233 is an apocalyptic number.

It is an amenable number.

81589421233 is a deficient number, since it is larger than the sum of its proper divisors (1).

81589421233 is an equidigital number, since it uses as much as digits as its factorization.

81589421233 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 414720, while the sum is 46.

The spelling of 81589421233 in words is "eighty-one billion, five hundred eighty-nine million, four hundred twenty-one thousand, two hundred thirty-three".