1908778653149 has 2 divisors, whose sum is σ = 1908778653150. Its totient is φ = 1908778653148.

The previous prime is 1908778653121. The next prime is 1908778653203. The reversal of 1908778653149 is 9413568778091.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1544258553124 + 364520100025 = 1242682^2 + 603755^2 .

It is a cyclic number.

It is not a de Polignac number, because 1908778653149 - 2³⁶ = 1840059176413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1908778653349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 954389326574 + 954389326575.

It is an arithmetic number, because the mean of its divisors is an integer number (954389326575).

Almost surely, 2^{1908778653149} is an apocalyptic number.

It is an amenable number.

1908778653149 is a deficient number, since it is larger than the sum of its proper divisors (1).

1908778653149 is an equidigital number, since it uses as much as digits as its factorization.

1908778653149 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 91445760, while the sum is 68.

The spelling of 1908778653149 in words is "one trillion, nine hundred eight billion, seven hundred seventy-eight million, six hundred fifty-three thousand, one hundred forty-nine".