51861984 has 48 divisors (see below), whose sum is σ = 138719952. Its totient is φ = 16959488.

The previous prime is 51861961. The next prime is 51862067. The reversal of 51861984 is 48916815.

51861984 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (48).

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 7 ways as a sum of consecutive naturals, for example, 9 + ... + 10184.

It is an arithmetic number, because the mean of its divisors is an integer number (2889999).

Almost surely, 2^51861984 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 51861984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69359976).

51861984 is an abundant number, since it is smaller than the sum of its proper divisors (86857968).

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

51861984 is a wasteful number, since it uses less digits than its factorization.

51861984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10259 (or 10251 counting only the distinct ones).

The product of its digits is 69120, while the sum is 42.

The square root of 51861984 is about 7201.5265048460. The cubic root of 51861984 is about 372.9206011355.

The spelling of 51861984 in words is "fifty-one million, eight hundred sixty-one thousand, nine hundred eighty-four".