51636 has 24 divisors (see below), whose sum is σ = 130144. Its totient is φ = 15840.

The previous prime is 51631. The next prime is 51637. The reversal of 51636 is 63615.

51636 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a nialpdrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51631) by changing a digit.

51636 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10 + ... + 321.

2⁵¹⁶³⁶ 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 51636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65072).

51636 is an abundant number, since it is smaller than the sum of its proper divisors (78508).

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

51636 is a wasteful number, since it uses less digits than its factorization.

51636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351 (or 349 counting only the distinct ones).

The product of its digits is 540, while the sum is 21.

The square root of 51636 is about 227.2355605974. The cubic root of 51636 is about 37.2378156327.

Subtracting from 51636 its sum of digits (21), we obtain a palindrome (51615).

The spelling of 51636 in words is "fifty-one thousand, six hundred thirty-six".