2778317354209 has 2 divisors, whose sum is σ = 2778317354210. Its totient is φ = 2778317354208.

The previous prime is 2778317354203. The next prime is 2778317354221. The reversal of 2778317354209 is 9024537138772.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2594080678225 + 184236675984 = 1610615^2 + 429228^2 .

It is a cyclic number.

It is not a de Polignac number, because 2778317354209 - 2³ = 2778317354201 is a prime.

It is not a weakly prime, because it can be changed into another prime (2778317354201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1389158677104 + 1389158677105.

It is an arithmetic number, because the mean of its divisors is an integer number (1389158677105).

Almost surely, 2^{2778317354209} is an apocalyptic number.

It is an amenable number.

2778317354209 is a deficient number, since it is larger than the sum of its proper divisors (1).

2778317354209 is an equidigital number, since it uses as much as digits as its factorization.

2778317354209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17781120, while the sum is 58.

The spelling of 2778317354209 in words is "two trillion, seven hundred seventy-eight billion, three hundred seventeen million, three hundred fifty-four thousand, two hundred nine".