8187409 has 2 divisors, whose sum is σ = 8187410. Its totient is φ = 8187408.

The previous prime is 8187373. The next prime is 8187419. The reversal of 8187409 is 9047818.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7579009 + 608400 = 2753^2 + 780^2 .

It is a cyclic number.

It is not a de Polignac number, because 8187409 - 2¹⁷ = 8056337 is a prime.

It is a super-2 number, since 2×8187409² = 134067332266562, which contains 22 as substring.

It is a Chen prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (8187419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4093704 + 4093705.

It is an arithmetic number, because the mean of its divisors is an integer number (4093705).

Almost surely, 2^8187409 is an apocalyptic number.

It is an amenable number.

8187409 is a deficient number, since it is larger than the sum of its proper divisors (1).

8187409 is an equidigital number, since it uses as much as digits as its factorization.

8187409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 8187409 is about 2861.3648841069. The cubic root of 8187409 is about 201.5497027590.

The spelling of 8187409 in words is "eight million, one hundred eighty-seven thousand, four hundred nine".