647778056 has 32 divisors (see below), whose sum is σ = 1234164600. Its totient is φ = 318689280.

The previous prime is 647778041. The next prime is 647778067. The reversal of 647778056 is 650877746.

It can be written as a sum of positive squares in 4 ways, for example, as 442429156 + 205348900 = 21034^2 + 14330^2 .

It is a junction number, because it is equal to n+sod(n) for n = 647777995 and 647778013.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 303200 + ... + 305328.

Almost surely, 2^647778056 is an apocalyptic number.

It is an amenable number.

647778056 is a deficient number, since it is larger than the sum of its proper divisors (586386544).

647778056 is a wasteful number, since it uses less digits than its factorization.

647778056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2729 (or 2725 counting only the distinct ones).

The product of its (nonzero) digits is 1975680, while the sum is 50.

The square root of 647778056 is about 25451.4843574987. The cubic root of 647778056 is about 865.2509350268.

The spelling of 647778056 in words is "six hundred forty-seven million, seven hundred seventy-eight thousand, fifty-six".