51304320 has 128 divisors (see below), whose sum is σ = 181764000. Its totient is φ = 13676544.

The previous prime is 51304291. The next prime is 51304333. The reversal of 51304320 is 2340315.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 51304293 and 51304302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15796 + ... + 18764.

Almost surely, 2^51304320 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 51304320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90882000).

51304320 is an abundant number, since it is smaller than the sum of its proper divisors (130459680).

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

51304320 is a wasteful number, since it uses less digits than its factorization.

51304320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2997 (or 2979 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 51304320 is about 7162.7034002533. The cubic root of 51304320 is about 371.5791285949.

Adding to 51304320 its reverse (2340315), we get a palindrome (53644635).

The spelling of 51304320 in words is "fifty-one million, three hundred four thousand, three hundred twenty".