255999853661 has 2 divisors, whose sum is σ = 255999853662. Its totient is φ = 255999853660.

The previous prime is 255999853607. The next prime is 255999853751. The reversal of 255999853661 is 166358999552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 204366380761 + 51633472900 = 452069^2 + 227230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-255999853661 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 255999853591 and 255999853600.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (255999850661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 127999926830 + 127999926831.

It is an arithmetic number, because the mean of its divisors is an integer number (127999926831).

Almost surely, 2^255999853661 is an apocalyptic number.

It is an amenable number.

255999853661 is a deficient number, since it is larger than the sum of its proper divisors (1).

255999853661 is an equidigital number, since it uses as much as digits as its factorization.

255999853661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 157464000, while the sum is 68.

The spelling of 255999853661 in words is "two hundred fifty-five billion, nine hundred ninety-nine million, eight hundred fifty-three thousand, six hundred sixty-one".