51635381616 has 960 divisors, whose sum is σ = 199667220480. Its totient is φ = 12070840320.

The previous prime is 51635381569. The next prime is 51635381621. The reversal of 51635381616 is 61618353615.

51635381616 is a `hidden beast` number, since 5 + 1 + 635 + 3 + 8 + 1 + 6 + 1 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 406577745 + ... + 406577871.

It is an arithmetic number, because the mean of its divisors is an integer number (207986688).

Almost surely, 2^51635381616 is an apocalyptic number.

51635381616 is a gapful number since it is divisible by the number (56) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51635381616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99833610240).

51635381616 is an abundant number, since it is smaller than the sum of its proper divisors (148031838864).

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

51635381616 is a wasteful number, since it uses less digits than its factorization.

51635381616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274 (or 265 counting only the distinct ones).

The product of its digits is 388800, while the sum is 45.

The spelling of 51635381616 in words is "fifty-one billion, six hundred thirty-five million, three hundred eighty-one thousand, six hundred sixteen".