2555566817 has 2 divisors, whose sum is σ = 2555566818. Its totient is φ = 2555566816.

The previous prime is 2555566799. The next prime is 2555566831. The reversal of 2555566817 is 7186655552.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2555403601 + 163216 = 50551^2 + 404^2 .

It is a cyclic number.

It is not a de Polignac number, because 2555566817 - 2¹⁴ = 2555550433 is a prime.

It is a super-3 number, since 3×2555566817³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (2555566877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1277783408 + 1277783409.

It is an arithmetic number, because the mean of its divisors is an integer number (1277783409).

Almost surely, 2^2555566817 is an apocalyptic number.

It is an amenable number.

2555566817 is a deficient number, since it is larger than the sum of its proper divisors (1).

2555566817 is an equidigital number, since it uses as much as digits as its factorization.

2555566817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2520000, while the sum is 50.

The square root of 2555566817 is about 50552.6143438695. The cubic root of 2555566817 is about 1367.1906514728.

The spelling of 2555566817 in words is "two billion, five hundred fifty-five million, five hundred sixty-six thousand, eight hundred seventeen".