51998993280 has 1280 divisors, whose sum is σ = 218956953600. Its totient is φ = 11645337600.

The previous prime is 51998993279. The next prime is 51998993317. The reversal of 51998993280 is 8239989915.

51998993280 is a `hidden beast` number, since 5 + 199 + 89 + 93 + 280 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 396938815 + ... + 396938945.

It is an arithmetic number, because the mean of its divisors is an integer number (171060120).

Almost surely, 2^51998993280 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 51998993280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109478476800).

51998993280 is an abundant number, since it is smaller than the sum of its proper divisors (166957960320).

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

51998993280 is a wasteful number, since it uses less digits than its factorization.

51998993280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 12597120, while the sum is 63.

The spelling of 51998993280 in words is "fifty-one billion, nine hundred ninety-eight million, nine hundred ninety-three thousand, two hundred eighty".