51611655611616 has 384 divisors, whose sum is σ = 145993521623040. Its totient is φ = 15924871987200.

The previous prime is 51611655611573. The next prime is 51611655611627. The reversal of 51611655611616 is 61611655611615.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5716204990 + ... + 5716214018.

It is an arithmetic number, because the mean of its divisors is an integer number (380191462560).

Almost surely, 2^{51611655611616} 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 51611655611616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72996760811520).

51611655611616 is an abundant number, since it is smaller than the sum of its proper divisors (94381866011424).

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

51611655611616 is a wasteful number, since it uses less digits than its factorization.

51611655611616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9610 (or 9602 counting only the distinct ones).

The product of its digits is 972000, while the sum is 51.

Subtracting 51611655611616 from its reverse (61611655611615), we obtain a palindrome (9999999999999).

The spelling of 51611655611616 in words is "fifty-one trillion, six hundred eleven billion, six hundred fifty-five million, six hundred eleven thousand, six hundred sixteen".