51310820 has 24 divisors (see below), whose sum is σ = 117548928. Its totient is φ = 18658400.

The previous prime is 51310801. The next prime is 51310829. The reversal of 51310820 is 2801315.

51310820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 51310792 and 51310801.

It is not an unprimeable number, because it can be changed into a prime (51310829) by changing a digit.

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, 116396 + ... + 116835.

It is an arithmetic number, because the mean of its divisors is an integer number (4897872).

Almost surely, 2^51310820 is an apocalyptic number.

It is an amenable number.

51310820 is an abundant number, since it is smaller than the sum of its proper divisors (66238108).

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

51310820 is a wasteful number, since it uses less digits than its factorization.

51310820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233251 (or 233249 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 51310820 is about 7163.1571251788. The cubic root of 51310820 is about 371.5948203361.

The spelling of 51310820 in words is "fifty-one million, three hundred ten thousand, eight hundred twenty".