51840009 has 12 divisors (see below), whose sum is σ = 80640196. Its totient is φ = 31901472.

The previous prime is 51840007. The next prime is 51840043. The reversal of 51840009 is 90004815.

It can be written as a sum of positive squares in 2 ways, for example, as 7683984 + 44156025 = 2772^2 + 6645^2 .

It is not a de Polignac number, because 51840009 - 2¹ = 51840007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51840007) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 221422 + ... + 221655.

Almost surely, 2^51840009 is an apocalyptic number.

It is an amenable number.

51840009 is a deficient number, since it is larger than the sum of its proper divisors (28800187).

51840009 is a wasteful number, since it uses less digits than its factorization.

51840009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443096 (or 443093 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 51840009 is about 7200.0006250000. Note that the first 3 decimals coincide. The cubic root of 51840009 is about 372.8679222925.

It can be divided in two parts, 5184000 and 9, that multiplied together give a cube (46656000 = 360³).

The spelling of 51840009 in words is "fifty-one million, eight hundred forty thousand, nine".