51216 has 40 divisors (see below), whose sum is σ = 145824. Its totient is φ = 15360.

The previous prime is 51203. The next prime is 51217. The reversal of 51216 is 61215.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 51195 and 51204.

It is not an unprimeable number, because it can be changed into a prime (51217) 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, 480 + ... + 576.

2⁵¹²¹⁶ 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 51216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72912).

51216 is an abundant number, since it is smaller than the sum of its proper divisors (94608).

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

51216 is a wasteful number, since it uses less digits than its factorization.

51216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119 (or 113 counting only the distinct ones).

The product of its digits is 60, while the sum is 15.

The square root of 51216 is about 226.3095225571. The cubic root of 51216 is about 37.1365782568.

Subtracting 51216 from its reverse (61215), we obtain a palindrome (9999).

It can be divided in two parts, 512 and 16, that multiplied together give a 13-th power (8192 = 2¹³).

The spelling of 51216 in words is "fifty-one thousand, two hundred sixteen".