87549809 has 2 divisors, whose sum is σ = 87549810. Its totient is φ = 87549808.

The previous prime is 87549793. The next prime is 87549829. The reversal of 87549809 is 90894578.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64240225 + 23309584 = 8015^2 + 4828^2 .

It is a cyclic number.

It is not a de Polignac number, because 87549809 - 2⁴ = 87549793 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (87549829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43774904 + 43774905.

It is an arithmetic number, because the mean of its divisors is an integer number (43774905).

Almost surely, 2^87549809 is an apocalyptic number.

It is an amenable number.

87549809 is a deficient number, since it is larger than the sum of its proper divisors (1).

87549809 is an equidigital number, since it uses as much as digits as its factorization.

87549809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 725760, while the sum is 50.

The square root of 87549809 is about 9356.8054911920. The cubic root of 87549809 is about 444.0362241500.

The spelling of 87549809 in words is "eighty-seven million, five hundred forty-nine thousand, eight hundred nine".