51561843 has 4 divisors (see below), whose sum is σ = 68749128. Its totient is φ = 34374560.

The previous prime is 51561827. The next prime is 51561857. The reversal of 51561843 is 34816515.

51561843 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51561843 - 2⁴ = 51561827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51561863) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 8593638 + ... + 8593643.

It is an arithmetic number, because the mean of its divisors is an integer number (17187282).

Almost surely, 2^51561843 is an apocalyptic number.

51561843 is a deficient number, since it is larger than the sum of its proper divisors (17187285).

51561843 is a wasteful number, since it uses less digits than its factorization.

51561843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17187284.

The product of its digits is 14400, while the sum is 33.

The square root of 51561843 is about 7180.6575604188. The cubic root of 51561843 is about 372.1998073909.

The spelling of 51561843 in words is "fifty-one million, five hundred sixty-one thousand, eight hundred forty-three".