51661680000 has 960 divisors, whose sum is σ = 209237022720. Its totient is φ = 11235840000.

The previous prime is 51661679969. The next prime is 51661680013. The reversal of 51661680000 is 8616615.

It is a tau number, because it is divible by the number of its divisors (960).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 270479905 + ... + 270480095.

It is an arithmetic number, because the mean of its divisors is an integer number (217955232).

Almost surely, 2^51661680000 is an apocalyptic number.

51661680000 is a gapful number since it is divisible by the number (50) 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 51661680000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104618511360).

51661680000 is an abundant number, since it is smaller than the sum of its proper divisors (157575342720).

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

51661680000 is a wasteful number, since it uses less digits than its factorization.

51661680000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265 (or 231 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The spelling of 51661680000 in words is "fifty-one billion, six hundred sixty-one million, six hundred eighty thousand".