51671309 has 2 divisors, whose sum is σ = 51671310. Its totient is φ = 51671308.

The previous prime is 51671287. The next prime is 51671339. The reversal of 51671309 is 90317615.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51337225 + 334084 = 7165^2 + 578^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51671309 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51671339) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25835654 + 25835655.

It is an arithmetic number, because the mean of its divisors is an integer number (25835655).

Almost surely, 2^51671309 is an apocalyptic number.

It is an amenable number.

51671309 is a deficient number, since it is larger than the sum of its proper divisors (1).

51671309 is an equidigital number, since it uses as much as digits as its factorization.

51671309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5670, while the sum is 32.

The square root of 51671309 is about 7188.2758016092. The cubic root of 51671309 is about 372.4630151109.

The spelling of 51671309 in words is "fifty-one million, six hundred seventy-one thousand, three hundred nine".