51551320 has 16 divisors (see below), whose sum is σ = 115990560. Its totient is φ = 20620512.

The previous prime is 51551263. The next prime is 51551333. The reversal of 51551320 is 2315515.

It is a junction number, because it is equal to n+sod(n) for n = 51551291 and 51551300.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 644352 + ... + 644431.

It is an arithmetic number, because the mean of its divisors is an integer number (7249410).

Almost surely, 2^51551320 is an apocalyptic number.

It is an amenable number.

51551320 is an abundant number, since it is smaller than the sum of its proper divisors (64439240).

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

51551320 is a wasteful number, since it uses less digits than its factorization.

51551320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1288794 (or 1288790 counting only the distinct ones).

The product of its (nonzero) digits is 750, while the sum is 22.

The square root of 51551320 is about 7179.9247906924. The cubic root of 51551320 is about 372.1744855326.

Adding to 51551320 its reverse (2315515), we get a palindrome (53866835).

The spelling of 51551320 in words is "fifty-one million, five hundred fifty-one thousand, three hundred twenty".