51558949856 has 48 divisors (see below), whose sum is σ = 106085718144. Its totient is φ = 24620052864.

The previous prime is 51558949831. The next prime is 51558949859. The reversal of 51558949856 is 65894985515.

It is a junction number, because it is equal to n+sod(n) for n = 51558949792 and 51558949801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51558949859) 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 7 ways as a sum of consecutive naturals, for example, 418775 + ... + 527721.

It is an arithmetic number, because the mean of its divisors is an integer number (2210119128).

Almost surely, 2^51558949856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51558949856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53042859072).

51558949856 is an abundant number, since it is smaller than the sum of its proper divisors (54526768288).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51558949856 is a wasteful number, since it uses less digits than its factorization.

51558949856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109623 (or 109615 counting only the distinct ones).

The product of its digits is 77760000, while the sum is 65.

The spelling of 51558949856 in words is "fifty-one billion, five hundred fifty-eight million, nine hundred forty-nine thousand, eight hundred fifty-six".