231776782085489 has 2 divisors, whose sum is σ = 231776782085490. Its totient is φ = 231776782085488.

The previous prime is 231776782085449. The next prime is 231776782085491. The reversal of 231776782085489 is 984580287677132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 227152131835489 + 4624650250000 = 15071567^2 + 2150500^2 .

It is a cyclic number.

It is not a de Polignac number, because 231776782085489 - 2¹⁶ = 231776782019953 is a prime.

Together with 231776782085491, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (231776782085419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115888391042744 + 115888391042745.

It is an arithmetic number, because the mean of its divisors is an integer number (115888391042745).

It is a 1-persistent number, because it is pandigital, but 2⋅231776782085489 = 463553564170978 is not.

Almost surely, 2^{231776782085489} is an apocalyptic number.

It is an amenable number.

231776782085489 is a deficient number, since it is larger than the sum of its proper divisors (1).

231776782085489 is an equidigital number, since it uses as much as digits as its factorization.

231776782085489 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2275983360, while the sum is 77.

The spelling of 231776782085489 in words is "two hundred thirty-one trillion, seven hundred seventy-six billion, seven hundred eighty-two million, eighty-five thousand, four hundred eighty-nine".