51561605280 has 192 divisors, whose sum is σ = 166637036160. Its totient is φ = 13397262336.

The previous prime is 51561605269. The next prime is 51561605287. The reversal of 51561605280 is 8250616515.

It is not an unprimeable number, because it can be changed into a prime (51561605287) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 2899456 + ... + 2917184.

It is an arithmetic number, because the mean of its divisors is an integer number (867901230).

Almost surely, 2^51561605280 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 51561605280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83318518080).

51561605280 is an abundant number, since it is smaller than the sum of its proper divisors (115075430880).

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

51561605280 is a wasteful number, since it uses less digits than its factorization.

51561605280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17903 (or 17895 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 39.

The spelling of 51561605280 in words is "fifty-one billion, five hundred sixty-one million, six hundred five thousand, two hundred eighty".