51115651648 has 28 divisors (see below), whose sum is σ = 101958203500. Its totient is φ = 25425395712.

The previous prime is 51115651579. The next prime is 51115651649. The reversal of 51115651648 is 84615651115.

It can be written as a sum of positive squares in 2 ways, for example, as 25628167744 + 25487483904 = 160088^2 + 159648^2 .

It is a super-3 number, since 3×51115651648³ (a number of 33 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (51115651649) 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 3 ways as a sum of consecutive naturals, for example, 2056773 + ... + 2081476.

Almost surely, 2^51115651648 is an apocalyptic number.

It is an amenable number.

51115651648 is a deficient number, since it is larger than the sum of its proper divisors (50842551852).

51115651648 is a wasteful number, since it uses less digits than its factorization.

51115651648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4138454 (or 4138444 counting only the distinct ones).

The product of its digits is 144000, while the sum is 43.

The spelling of 51115651648 in words is "fifty-one billion, one hundred fifteen million, six hundred fifty-one thousand, six hundred forty-eight".