647471075656 has 8 divisors (see below), whose sum is σ = 1214008266870. Its totient is φ = 323735537824.

The previous prime is 647471075653. The next prime is 647471075677. The reversal of 647471075656 is 656570174746.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 371814574756 + 275656500900 = 609766^2 + 525030^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×647471075656² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 647471075656.

It is not an unprimeable number, because it can be changed into a prime (647471075653) by changing a digit.

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 as a sum of consecutive naturals, namely, 40466942221 + ... + 40466942236.

Almost surely, 2^647471075656 is an apocalyptic number.

It is an amenable number.

647471075656 is a deficient number, since it is larger than the sum of its proper divisors (566537191214).

647471075656 is a wasteful number, since it uses less digits than its factorization.

647471075656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80933884463 (or 80933884459 counting only the distinct ones).

The product of its (nonzero) digits is 29635200, while the sum is 58.

The spelling of 647471075656 in words is "six hundred forty-seven billion, four hundred seventy-one million, seventy-five thousand, six hundred fifty-six".