51383440 has 40 divisors (see below), whose sum is σ = 120403008. Its totient is φ = 20392320.

The previous prime is 51383419. The next prime is 51383441. The reversal of 51383440 is 4438315.

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 51383399 and 51383408.

It is not an unprimeable number, because it can be changed into a prime (51383441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8029 + ... + 12931.

Almost surely, 2^51383440 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 51383440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (60201504).

51383440 is an abundant number, since it is smaller than the sum of its proper divisors (69019568).

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

51383440 is a wasteful number, since it uses less digits than its factorization.

51383440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5047 (or 5041 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 51383440 is about 7168.2243268469. The cubic root of 51383440 is about 371.7700432564.

The spelling of 51383440 in words is "fifty-one million, three hundred eighty-three thousand, four hundred forty".