51487663656 has 512 divisors, whose sum is σ = 166379028480. Its totient is φ = 13047091200.

The previous prime is 51487663637. The next prime is 51487663663. The reversal of 51487663656 is 65636678415.

It is a junction number, because it is equal to n+sod(n) for n = 51487663596 and 51487663605.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 129691650 + ... + 129692046.

It is an arithmetic number, because the mean of its divisors is an integer number (324959040).

Almost surely, 2^51487663656 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 51487663656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83189514240).

51487663656 is an abundant number, since it is smaller than the sum of its proper divisors (114891364824).

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

51487663656 is a wasteful number, since it uses less digits than its factorization.

51487663656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537 (or 533 counting only the distinct ones).

The product of its digits is 21772800, while the sum is 57.

The spelling of 51487663656 in words is "fifty-one billion, four hundred eighty-seven million, six hundred sixty-three thousand, six hundred fifty-six".