56009309 has 2 divisors, whose sum is σ = 56009310. Its totient is φ = 56009308.

The previous prime is 56009293. The next prime is 56009311. The reversal of 56009309 is 90390065.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43428100 + 12581209 = 6590^2 + 3547^2 .

It is a cyclic number.

It is not a de Polignac number, because 56009309 - 2⁴ = 56009293 is a prime.

Together with 56009311, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56009329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28004654 + 28004655.

It is an arithmetic number, because the mean of its divisors is an integer number (28004655).

Almost surely, 2^56009309 is an apocalyptic number.

It is an amenable number.

56009309 is a deficient number, since it is larger than the sum of its proper divisors (1).

56009309 is an equidigital number, since it uses as much as digits as its factorization.

56009309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7290, while the sum is 32.

The square root of 56009309 is about 7483.9367314268. The cubic root of 56009309 is about 382.6074347566.

The spelling of 56009309 in words is "fifty-six million, nine thousand, three hundred nine".