51856853841 has 27 divisors (see below), whose sum is σ = 81123331419. Its totient is φ = 31906444752.

The previous prime is 51856853813. The next prime is 51856853891. The reversal of 51856853841 is 14835865815.

The square root of 51856853841 is 227721.

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

51856853841 is a `hidden beast` number, since 5 + 1 + 8 + 5 + 68 + 538 + 41 = 666.

It can be written as a sum of positive squares in only one way, i.e., 7671132225 + 44185721616 = 87585^2 + 210204^2 .

It is not a de Polignac number, because 51856853841 - 2²¹ = 51854756689 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51856853891) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 8878200 + ... + 8884038.

Almost surely, 2^51856853841 is an apocalyptic number.

51856853841 is the 227721-st square number.

51856853841 is the 113861-st centered octagonal number.

It is an amenable number.

51856853841 is a deficient number, since it is larger than the sum of its proper divisors (29266477578).

51856853841 is an frugal number, since it uses more digits than its factorization.

51856853841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11710 (or 5855 counting only the distinct ones).

The product of its digits is 4608000, while the sum is 54.

The spelling of 51856853841 in words is "fifty-one billion, eight hundred fifty-six million, eight hundred fifty-three thousand, eight hundred forty-one".