51654969940 has 168 divisors, whose sum is σ = 131091415560. Its totient is φ = 17076987648.

The previous prime is 51654969923. The next prime is 51654969959. The reversal of 51654969940 is 4996945615.

It can be written as a sum of positive squares in 4 ways, for example, as 7590242884 + 44064727056 = 87122^2 + 209916^2 .

It is a Harshad number since it is a multiple of its sum of digits (58).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 68236042 + ... + 68236798.

It is an arithmetic number, because the mean of its divisors is an integer number (780306045).

Almost surely, 2^51654969940 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 51654969940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65545707780).

51654969940 is an abundant number, since it is smaller than the sum of its proper divisors (79436445620).

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

51654969940 is an frugal number, since it uses more digits than its factorization.

51654969940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 837 (or 800 counting only the distinct ones).

The product of its (nonzero) digits is 10497600, while the sum is 58.

The spelling of 51654969940 in words is "fifty-one billion, six hundred fifty-four million, nine hundred sixty-nine thousand, nine hundred forty".