1968856261 has 2 divisors, whose sum is σ = 1968856262. Its totient is φ = 1968856260.

The previous prime is 1968856259. The next prime is 1968856271. The reversal of 1968856261 is 1626588691.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1949222500 + 19633761 = 44150^2 + 4431^2 .

It is a cyclic number.

It is not a de Polignac number, because 1968856261 - 2¹ = 1968856259 is a prime.

Together with 1968856259, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1968856199 and 1968856208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1968856271) 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, 984428130 + 984428131.

It is an arithmetic number, because the mean of its divisors is an integer number (984428131).

Almost surely, 2^1968856261 is an apocalyptic number.

It is an amenable number.

1968856261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1968856261 is an equidigital number, since it uses as much as digits as its factorization.

1968856261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1244160, while the sum is 52.

The square root of 1968856261 is about 44371.7957829070. The cubic root of 1968856261 is about 1253.3470322477.

The spelling of 1968856261 in words is "one billion, nine hundred sixty-eight million, eight hundred fifty-six thousand, two hundred sixty-one".