647760561 has 16 divisors (see below), whose sum is σ = 987696000. Its totient is φ = 369911808.

The previous prime is 647760493. The next prime is 647760577. The reversal of 647760561 is 165067746.

It is not a de Polignac number, because 647760561 - 2¹¹ = 647758513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (647760361) 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 in 15 ways as a sum of consecutive naturals, for example, 26865 + ... + 44913.

It is an arithmetic number, because the mean of its divisors is an integer number (61731000).

Almost surely, 2^647760561 is an apocalyptic number.

It is an amenable number.

647760561 is a deficient number, since it is larger than the sum of its proper divisors (339935439).

647760561 is a wasteful number, since it uses less digits than its factorization.

647760561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19768.

The product of its (nonzero) digits is 211680, while the sum is 42.

The square root of 647760561 is about 25451.1406620607. The cubic root of 647760561 is about 865.2431454754.

The spelling of 647760561 in words is "six hundred forty-seven million, seven hundred sixty thousand, five hundred sixty-one".