51821633612815 has 64 divisors (see below), whose sum is σ = 71497081700352. Its totient is φ = 35689187776000.

The previous prime is 51821633612797. The next prime is 51821633612839.

It is a happy number.

51821633612815 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 51821633612815 - 2³⁹ = 51271877798927 is a prime.

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 63 ways as a sum of consecutive naturals, for example, 1888736277 + ... + 1888763713.

It is an arithmetic number, because the mean of its divisors is an integer number (1117141901568).

Almost surely, 2^{51821633612815} is an apocalyptic number.

51821633612815 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51821633612815 is a deficient number, since it is larger than the sum of its proper divisors (19675448087537).

51821633612815 is a wasteful number, since it uses less digits than its factorization.

51821633612815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42360.

The product of its digits is 2073600, while the sum is 52.

It can be divided in two parts, 5182163 and 3612815, that added together give a palindrome (8794978).

The spelling of 51821633612815 in words is "fifty-one trillion, eight hundred twenty-one billion, six hundred thirty-three million, six hundred twelve thousand, eight hundred fifteen".