51513100240 has 240 divisors, whose sum is σ = 141778425600. Its totient is φ = 17352631296.

The previous prime is 51513100237. The next prime is 51513100259. The reversal of 51513100240 is 4200131515.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 122942751 + ... + 122943169.

It is an arithmetic number, because the mean of its divisors is an integer number (590743440).

Almost surely, 2^51513100240 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 51513100240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70889212800).

51513100240 is an abundant number, since it is smaller than the sum of its proper divisors (90265325360).

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

51513100240 is a wasteful number, since it uses less digits than its factorization.

51513100240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 922 (or 909 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

Adding to 51513100240 its reverse (4200131515), we get a palindrome (55713231755).

The spelling of 51513100240 in words is "fifty-one billion, five hundred thirteen million, one hundred thousand, two hundred forty".