51328128 has 64 divisors (see below), whose sum is σ = 137088000. Its totient is φ = 17015808.

The previous prime is 51328127. The next prime is 51328129. The reversal of 51328128 is 82182315.

It is an interprime number because it is at equal distance from previous prime (51328127) and next prime (51328129).

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 51328095 and 51328104.

It is not an unprimeable number, because it can be changed into a prime (51328127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133825 + ... + 134207.

It is an arithmetic number, because the mean of its divisors is an integer number (2142000).

Almost surely, 2^51328128 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 51328128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68544000).

51328128 is an abundant number, since it is smaller than the sum of its proper divisors (85759872).

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

51328128 is a wasteful number, since it uses less digits than its factorization.

51328128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 749 (or 737 counting only the distinct ones).

The product of its digits is 3840, while the sum is 30.

The square root of 51328128 is about 7164.3651498231. The cubic root of 51328128 is about 371.6365973604.

The spelling of 51328128 in words is "fifty-one million, three hundred twenty-eight thousand, one hundred twenty-eight".