255687779 has 2 divisors, whose sum is σ = 255687780. Its totient is φ = 255687778.

The previous prime is 255687727. The next prime is 255687821. The reversal of 255687779 is 977786552.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-255687779 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (255687079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 127843889 + 127843890.

It is an arithmetic number, because the mean of its divisors is an integer number (127843890).

Almost surely, 2^255687779 is an apocalyptic number.

255687779 is a deficient number, since it is larger than the sum of its proper divisors (1).

255687779 is an equidigital number, since it uses as much as digits as its factorization.

255687779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7408800, while the sum is 56.

The square root of 255687779 is about 15990.2401170214. The cubic root of 255687779 is about 634.7021803869.

The spelling of 255687779 in words is "two hundred fifty-five million, six hundred eighty-seven thousand, seven hundred seventy-nine".