51330988820 has 24 divisors (see below), whose sum is σ = 109562211528. Its totient is φ = 20195798400.

The previous prime is 51330988811. The next prime is 51330988823. The reversal of 51330988820 is 2888903315.

It can be written as a sum of positive squares in 4 ways, for example, as 166358404 + 51164630416 = 12898^2 + 226196^2 .

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51330988823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21036071 + ... + 21038510.

It is an arithmetic number, because the mean of its divisors is an integer number (4565092147).

Almost surely, 2^51330988820 is an apocalyptic number.

It is an amenable number.

51330988820 is an abundant number, since it is smaller than the sum of its proper divisors (58231222708).

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

51330988820 is a wasteful number, since it uses less digits than its factorization.

51330988820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42074651 (or 42074649 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 47.

The spelling of 51330988820 in words is "fifty-one billion, three hundred thirty million, nine hundred eighty-eight thousand, eight hundred twenty".