8294778649 has 2 divisors, whose sum is σ = 8294778650. Its totient is φ = 8294778648.

The previous prime is 8294778641. The next prime is 8294778749. The reversal of 8294778649 is 9468774928.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5439800025 + 2854978624 = 73755^2 + 53432^2 .

It is a cyclic number.

It is not a de Polignac number, because 8294778649 - 2³ = 8294778641 is a prime.

It is not a weakly prime, because it can be changed into another prime (8294778641) 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, 4147389324 + 4147389325.

It is an arithmetic number, because the mean of its divisors is an integer number (4147389325).

Almost surely, 2^8294778649 is an apocalyptic number.

It is an amenable number.

8294778649 is a deficient number, since it is larger than the sum of its proper divisors (1).

8294778649 is an equidigital number, since it uses as much as digits as its factorization.

8294778649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48771072, while the sum is 64.

The square root of 8294778649 is about 91075.6753968918. The cubic root of 8294778649 is about 2024.2691992006.

It can be divided in two parts, 82947 and 78649, that added together give a triangular number (161596 = T₅₆₈).

The spelling of 8294778649 in words is "eight billion, two hundred ninety-four million, seven hundred seventy-eight thousand, six hundred forty-nine".