1909782898409 has 2 divisors, whose sum is σ = 1909782898410. Its totient is φ = 1909782898408.

The previous prime is 1909782898399. The next prime is 1909782898427. The reversal of 1909782898409 is 9048982879091.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1170994515625 + 738788382784 = 1082125^2 + 859528^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1909782898409 is a prime.

It is not a weakly prime, because it can be changed into another prime (1909782898459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 954891449204 + 954891449205.

It is an arithmetic number, because the mean of its divisors is an integer number (954891449205).

Almost surely, 2^{1909782898409} is an apocalyptic number.

It is an amenable number.

1909782898409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1909782898409 is an equidigital number, since it uses as much as digits as its factorization.

1909782898409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 188116992, while the sum is 74.

The spelling of 1909782898409 in words is "one trillion, nine hundred nine billion, seven hundred eighty-two million, eight hundred ninety-eight thousand, four hundred nine".