51312322520 has 48 divisors (see below), whose sum is σ = 117202029840. Its totient is φ = 20218516032.

The previous prime is 51312322519. The next prime is 51312322531. The reversal of 51312322520 is 2522321315.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 51312322520.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36677 + ... + 322443.

It is an arithmetic number, because the mean of its divisors is an integer number (2441708955).

Almost surely, 2^51312322520 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 51312322520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58601014920).

51312322520 is an abundant number, since it is smaller than the sum of its proper divisors (65889707320).

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

51312322520 is a wasteful number, since it uses less digits than its factorization.

51312322520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285912 (or 285841 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 26.

Adding to 51312322520 its reverse (2522321315), we get a palindrome (53834643835).

The spelling of 51312322520 in words is "fifty-one billion, three hundred twelve million, three hundred twenty-two thousand, five hundred twenty".