1968519409 has 2 divisors, whose sum is σ = 1968519410. Its totient is φ = 1968519408.

The previous prime is 1968519407. The next prime is 1968519433. The reversal of 1968519409 is 9049158691.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1508545600 + 459973809 = 38840^2 + 21447^2 .

It is a cyclic number.

It is not a de Polignac number, because 1968519409 - 2¹ = 1968519407 is a prime.

Together with 1968519407, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1968519407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 984259704 + 984259705.

It is an arithmetic number, because the mean of its divisors is an integer number (984259705).

Almost surely, 2^1968519409 is an apocalyptic number.

It is an amenable number.

1968519409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1968519409 is an equidigital number, since it uses as much as digits as its factorization.

1968519409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 699840, while the sum is 52.

The square root of 1968519409 is about 44367.9998309592. Note that the first 3 decimals coincide. The cubic root of 1968519409 is about 1253.2755497085.

The spelling of 1968519409 in words is "one billion, nine hundred sixty-eight million, five hundred nineteen thousand, four hundred nine".