51620 has 24 divisors (see below), whose sum is σ = 113400. Its totient is φ = 19712.

The previous prime is 51613. The next prime is 51631. The reversal of 51620 is 2615.

It can be written as a sum of positive squares in 4 ways, for example, as 1444 + 50176 = 38^2 + 224^2 .

It is a junction number, because it is equal to n+sod(n) for n = 51595 and 51604.

It is an unprimeable number.

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, 536 + ... + 624.

It is an arithmetic number, because the mean of its divisors is an integer number (4725).

2⁵¹⁶²⁰ 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 51620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56700).

51620 is an abundant number, since it is smaller than the sum of its proper divisors (61780).

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

51620 is a wasteful number, since it uses less digits than its factorization.

51620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127 (or 125 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 51620 is about 227.2003521124. The cubic root of 51620 is about 37.2339690489.

It can be divided in two parts, 5 and 1620, that multiplied together give a square (8100 = 90²).

The spelling of 51620 in words is "fifty-one thousand, six hundred twenty".