51978891888 has 960 divisors, whose sum is σ = 206272512000. Its totient is φ = 12345177600.

The previous prime is 51978891863. The next prime is 51978891889. The reversal of 51978891888 is 88819887915.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51978891889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 137147283 + ... + 137147661.

It is an arithmetic number, because the mean of its divisors is an integer number (214867200).

Almost surely, 2^51978891888 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 51978891888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103136256000).

51978891888 is an abundant number, since it is smaller than the sum of its proper divisors (154293620112).

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

51978891888 is a wasteful number, since it uses less digits than its factorization.

51978891888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 471 (or 452 counting only the distinct ones).

The product of its digits is 92897280, while the sum is 72.

The spelling of 51978891888 in words is "fifty-one billion, nine hundred seventy-eight million, eight hundred ninety-one thousand, eight hundred eighty-eight".