51173678656 has 21 divisors (see below), whose sum is σ = 101551359889. Its totient is φ = 25585934464.

The previous prime is 51173678651. The next prime is 51173678663. The reversal of 51173678656 is 65687637115.

It is a happy number.

The square root of 51173678656 is 226216.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 19209960000 + 31963718656 = 138600^2 + 178784^2 .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51173678597 and 51173678606.

It is not an unprimeable number, because it can be changed into a prime (51173678651) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1795590 + ... + 1823866.

Almost surely, 2^51173678656 is an apocalyptic number.

51173678656 is the 226216-th square number.

It is an amenable number.

51173678656 is a deficient number, since it is larger than the sum of its proper divisors (50377681233).

51173678656 is an frugal number, since it uses more digits than its factorization.

51173678656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56566 (or 28279 counting only the distinct ones).

The product of its digits is 6350400, while the sum is 55.

The spelling of 51173678656 in words is "fifty-one billion, one hundred seventy-three million, six hundred seventy-eight thousand, six hundred fifty-six".