51909636865 has 16 divisors (see below), whose sum is σ = 64310478336. Its totient is φ = 40182163200.

The previous prime is 51909636817. The next prime is 51909636881. The reversal of 51909636865 is 56863690915.

It is not a de Polignac number, because 51909636865 - 2²³ = 51901248257 is a prime.

It is a super-2 number, since 2×51909636865² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1231834 + ... + 1273276.

It is an arithmetic number, because the mean of its divisors is an integer number (4019404896).

Almost surely, 2^51909636865 is an apocalyptic number.

It is an amenable number.

51909636865 is a deficient number, since it is larger than the sum of its proper divisors (12400841471).

51909636865 is a wasteful number, since it uses less digits than its factorization.

51909636865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49560.

The product of its (nonzero) digits is 10497600, while the sum is 58.

The spelling of 51909636865 in words is "fifty-one billion, nine hundred nine million, six hundred thirty-six thousand, eight hundred sixty-five".