278620812289 has 2 divisors, whose sum is σ = 278620812290. Its totient is φ = 278620812288.

The previous prime is 278620812181. The next prime is 278620812307. The reversal of 278620812289 is 982218026872.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 274882101264 + 3738711025 = 524292^2 + 61145^2 .

It is a cyclic number.

It is not a de Polignac number, because 278620812289 - 2¹⁷ = 278620681217 is a prime.

It is not a weakly prime, because it can be changed into another prime (278620812089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139310406144 + 139310406145.

It is an arithmetic number, because the mean of its divisors is an integer number (139310406145).

Almost surely, 2^278620812289 is an apocalyptic number.

It is an amenable number.

278620812289 is a deficient number, since it is larger than the sum of its proper divisors (1).

278620812289 is an equidigital number, since it uses as much as digits as its factorization.

278620812289 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3096576, while the sum is 55.

The spelling of 278620812289 in words is "two hundred seventy-eight billion, six hundred twenty million, eight hundred twelve thousand, two hundred eighty-nine".