51636520 has 64 divisors (see below), whose sum is σ = 126000000. Its totient is φ = 18931968.

The previous prime is 51636517. The next prime is 51636527. The reversal of 51636520 is 2563615.

It is not an unprimeable number, because it can be changed into a prime (51636527) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 103231 + ... + 103729.

It is an arithmetic number, because the mean of its divisors is an integer number (1968750).

Almost surely, 2^51636520 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 51636520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63000000).

51636520 is an abundant number, since it is smaller than the sum of its proper divisors (74363480).

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

51636520 is a wasteful number, since it uses less digits than its factorization.

51636520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722 (or 718 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 51636520 is about 7185.8555510113. The cubic root of 51636520 is about 372.3794063334.

The spelling of 51636520 in words is "fifty-one million, six hundred thirty-six thousand, five hundred twenty".