778216441 has 2 divisors, whose sum is σ = 778216442. Its totient is φ = 778216440.

The previous prime is 778216433. The next prime is 778216469. The reversal of 778216441 is 144612877.

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., 734193216 + 44023225 = 27096^2 + 6635^2 .

It is an emirp because it is prime and its reverse (144612877) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 778216441 - 2³ = 778216433 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 778216394 and 778216403.

It is not a weakly prime, because it can be changed into another prime (778216141) 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, 389108220 + 389108221.

It is an arithmetic number, because the mean of its divisors is an integer number (389108221).

Almost surely, 2^778216441 is an apocalyptic number.

It is an amenable number.

778216441 is a deficient number, since it is larger than the sum of its proper divisors (1).

778216441 is an equidigital number, since it uses as much as digits as its factorization.

778216441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 75264, while the sum is 40.

The square root of 778216441 is about 27896.5309850526. The cubic root of 778216441 is about 919.8142508581.

The spelling of 778216441 in words is "seven hundred seventy-eight million, two hundred sixteen thousand, four hundred forty-one".