56171309 has 2 divisors, whose sum is σ = 56171310. Its totient is φ = 56171308.

The previous prime is 56171273. The next prime is 56171321. The reversal of 56171309 is 90317165.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55547209 + 624100 = 7453^2 + 790^2 .

It is a cyclic number.

It is not a de Polignac number, because 56171309 - 2⁸ = 56171053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56171369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28085654 + 28085655.

It is an arithmetic number, because the mean of its divisors is an integer number (28085655).

Almost surely, 2^56171309 is an apocalyptic number.

It is an amenable number.

56171309 is a deficient number, since it is larger than the sum of its proper divisors (1).

56171309 is an equidigital number, since it uses as much as digits as its factorization.

56171309 is an evil number, because the sum of its binary digits is even.

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

The square root of 56171309 is about 7494.7520973012. The cubic root of 56171309 is about 382.9759612424.

The spelling of 56171309 in words is "fifty-six million, one hundred seventy-one thousand, three hundred nine".