51278438688 has 48 divisors (see below), whose sum is σ = 135183668256. Its totient is φ = 17019445760.

The previous prime is 51278438633. The next prime is 51278438749. The reversal of 51278438688 is 88683487215.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×51278438688² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1123878 + ... + 1168613.

It is an arithmetic number, because the mean of its divisors is an integer number (2816326422).

Almost surely, 2^51278438688 is an apocalyptic number.

It is an amenable number.

51278438688 is an abundant number, since it is smaller than the sum of its proper divisors (83905229568).

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

51278438688 is a wasteful number, since it uses less digits than its factorization.

51278438688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2292737 (or 2292729 counting only the distinct ones).

The product of its digits is 20643840, while the sum is 60.

The spelling of 51278438688 in words is "fifty-one billion, two hundred seventy-eight million, four hundred thirty-eight thousand, six hundred eighty-eight".