51805697985 has 64 divisors (see below), whose sum is σ = 92683008000. Its totient is φ = 27454956480.

The previous prime is 51805697959. The next prime is 51805698001. The reversal of 51805697985 is 58979650815.

It is not a de Polignac number, because 51805697985 - 2⁶ = 51805697921 is a prime.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 26176726 + ... + 26178704.

It is an arithmetic number, because the mean of its divisors is an integer number (1448172000).

Almost surely, 2^51805697985 is an apocalyptic number.

It is an amenable number.

51805697985 is a deficient number, since it is larger than the sum of its proper divisors (40877310015).

51805697985 is a wasteful number, since it uses less digits than its factorization.

51805697985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3123 (or 3117 counting only the distinct ones).

The product of its (nonzero) digits is 27216000, while the sum is 63.

The spelling of 51805697985 in words is "fifty-one billion, eight hundred five million, six hundred ninety-seven thousand, nine hundred eighty-five".