51951889920 has 640 divisors, whose sum is σ = 200815718400. Its totient is φ = 11205476352.

The previous prime is 51951889919. The next prime is 51951889933. The reversal of 51951889920 is 2998815915.

It is a tau number, because it is divible by the number of its divisors (640).

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 73274526 + ... + 73275234.

It is an arithmetic number, because the mean of its divisors is an integer number (313774560).

Almost surely, 2^51951889920 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 51951889920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100407859200).

51951889920 is an abundant number, since it is smaller than the sum of its proper divisors (148863828480).

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

51951889920 is a wasteful number, since it uses less digits than its factorization.

51951889920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 818 (or 802 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 57.

The spelling of 51951889920 in words is "fifty-one billion, nine hundred fifty-one million, eight hundred eighty-nine thousand, nine hundred twenty".