8131409 has 16 divisors (see below), whose sum is σ = 9664704. Its totient is φ = 6744000.

The previous prime is 8131399. The next prime is 8131421. The reversal of 8131409 is 9041318.

It is a cyclic number.

It is not a de Polignac number, because 8131409 - 2⁸ = 8131153 is a prime.

It is a super-2 number, since 2×8131409² = 132239624650562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8131469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14162 + ... + 14724.

It is an arithmetic number, because the mean of its divisors is an integer number (604044).

Almost surely, 2^8131409 is an apocalyptic number.

It is an amenable number.

8131409 is a deficient number, since it is larger than the sum of its proper divisors (1533295).

8131409 is a wasteful number, since it uses less digits than its factorization.

8131409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 8131409 is about 2851.5625541096. The cubic root of 8131409 is about 201.0891331784.

Subtracting 8131409 from its reverse (9041318), we obtain a palindrome (909909).

It can be divided in two parts, 813 and 1409, that added together give a palindrome (2222).

The spelling of 8131409 in words is "eight million, one hundred thirty-one thousand, four hundred nine".