51851815815 has 32 divisors (see below), whose sum is σ = 84964557312. Its totient is φ = 26994800000.

The previous prime is 51851815801. The next prime is 51851815823.

51851815815 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 51851815815 - 2⁹ = 51851815303 is a prime.

It is a super-2 number, since 2×51851815815² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 133461 + ... + 348590.

It is an arithmetic number, because the mean of its divisors is an integer number (2655142416).

Almost surely, 2^51851815815 is an apocalyptic number.

51851815815 is a deficient number, since it is larger than the sum of its proper divisors (33112741497).

51851815815 is a wasteful number, since it uses less digits than its factorization.

51851815815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 482231.

The product of its digits is 320000, while the sum is 48.

The spelling of 51851815815 in words is "fifty-one billion, eight hundred fifty-one million, eight hundred fifteen thousand, eight hundred fifteen".