51768640 has 168 divisors, whose sum is σ = 155667456. Its totient is φ = 16051200.

The previous prime is 51768617. The next prime is 51768643. The reversal of 51768640 is 4686715.

It is a self number, because there is not a number n which added to its sum of digits gives 51768640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51768643) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 270945 + ... + 271135.

It is an arithmetic number, because the mean of its divisors is an integer number (926592).

Almost surely, 2^51768640 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 51768640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77833728).

51768640 is an abundant number, since it is smaller than the sum of its proper divisors (103898816).

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

51768640 is a wasteful number, since it uses less digits than its factorization.

51768640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 51768640 is about 7195.0427378856. The cubic root of 51768640 is about 372.6967325580.

The spelling of 51768640 in words is "fifty-one million, seven hundred sixty-eight thousand, six hundred forty".