51803809 has 8 divisors (see below), whose sum is σ = 52501032. Its totient is φ = 51110400.

The previous prime is 51803803. The next prime is 51803813. The reversal of 51803809 is 90830815.

51803809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 34398225 + 17405584 = 5865^2 + 4172^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51803809 - 2¹⁷ = 51672737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51803803) 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 7 ways as a sum of consecutive naturals, for example, 34927 + ... + 36379.

It is an arithmetic number, because the mean of its divisors is an integer number (6562629).

Almost surely, 2^51803809 is an apocalyptic number.

It is an amenable number.

51803809 is a deficient number, since it is larger than the sum of its proper divisors (697223).

51803809 is a wasteful number, since it uses less digits than its factorization.

51803809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1907.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 51803809 is about 7197.4862973124. The cubic root of 51803809 is about 372.7811105672.

The spelling of 51803809 in words is "fifty-one million, eight hundred three thousand, eight hundred nine".