56909 has 2 divisors, whose sum is σ = 56910. Its totient is φ = 56908.
The previous prime is 56897. The next prime is 56911. The reversal of 56909 is 90965.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 42025 + 14884 = 205^2 + 122^2 .
It is a cyclic number.
It is not a de Polignac number, because 56909 - 24 = 56893 is a prime.
It is a Sophie Germain prime.
Together with 56911, it forms a pair of twin primes.
It is a Chen prime.
It is an alternating number because its digits alternate between odd and even.
It is a Curzon number.
It is a plaindrome in base 15.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (56929) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28454 + 28455.
It is an arithmetic number, because the mean of its divisors is an integer number (28455).
256909 is an apocalyptic number.
It is an amenable number.
56909 is a deficient number, since it is larger than the sum of its proper divisors (1).
56909 is an equidigital number, since it uses as much as digits as its factorization.
56909 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 2430, while the sum is 29.
The square root of 56909 is about 238.5560730730. The cubic root of 56909 is about 38.4645200765.
The spelling of 56909 in words is "fifty-six thousand, nine hundred nine".
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