647724871 has 16 divisors (see below), whose sum is σ = 697213440. Its totient is φ = 599564160.

The previous prime is 647724863. The next prime is 647724893. The reversal of 647724871 is 178427746.

It is not a de Polignac number, because 647724871 - 2³ = 647724863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647724841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 411516 + ... + 413086.

It is an arithmetic number, because the mean of its divisors is an integer number (43575840).

Almost surely, 2^647724871 is an apocalyptic number.

647724871 is a deficient number, since it is larger than the sum of its proper divisors (49488569).

647724871 is a wasteful number, since it uses less digits than its factorization.

647724871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1974.

The product of its digits is 526848, while the sum is 46.

The square root of 647724871 is about 25450.4395050459. The cubic root of 647724871 is about 865.2272542666.

The spelling of 647724871 in words is "six hundred forty-seven million, seven hundred twenty-four thousand, eight hundred seventy-one".