778548641 has 12 divisors (see below), whose sum is σ = 855060948. Its totient is φ = 704437344.

The previous prime is 778548629. The next prime is 778548647. The reversal of 778548641 is 146845877.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 326561041 + 451987600 = 18071^2 + 21260^2 .

It is not a de Polignac number, because 778548641 - 2¹⁰ = 778547617 is a prime.

It is a super-2 number, since 2×778548641² = 1212275972805893762, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 778548641.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778548647) 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 in 11 ways as a sum of consecutive naturals, for example, 731876 + ... + 732938.

It is an arithmetic number, because the mean of its divisors is an integer number (71255079).

Almost surely, 2^778548641 is an apocalyptic number.

It is an amenable number.

778548641 is a deficient number, since it is larger than the sum of its proper divisors (76512307).

778548641 is an equidigital number, since it uses as much as digits as its factorization.

778548641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2192 (or 1129 counting only the distinct ones).

The product of its digits is 1505280, while the sum is 50.

The square root of 778548641 is about 27902.4844951126. The cubic root of 778548641 is about 919.9451136916.

The spelling of 778548641 in words is "seven hundred seventy-eight million, five hundred forty-eight thousand, six hundred forty-one".