51647568 has 80 divisors (see below), whose sum is σ = 155644800. Its totient is φ = 14751744.

The previous prime is 51647551. The next prime is 51647569. The reversal of 51647568 is 86574615.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51647569) 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, 14896 + ... + 18032.

It is an arithmetic number, because the mean of its divisors is an integer number (1945560).

Almost surely, 2^51647568 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 51647568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77822400).

51647568 is an abundant number, since it is smaller than the sum of its proper divisors (103997232).

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

51647568 is a wasteful number, since it uses less digits than its factorization.

51647568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3169 (or 3149 counting only the distinct ones).

The product of its digits is 201600, while the sum is 42.

The square root of 51647568 is about 7186.6242422990. The cubic root of 51647568 is about 372.4059621787.

It can be divided in two parts, 516 and 47568, that added together give a palindrome (48084).

The spelling of 51647568 in words is "fifty-one million, six hundred forty-seven thousand, five hundred sixty-eight".