82187409 has 4 divisors (see below), whose sum is σ = 109583216. Its totient is φ = 54791604.

The previous prime is 82187383. The next prime is 82187419. The reversal of 82187409 is 90478128.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 82187409 - 2⁵ = 82187377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82187419) 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 3 ways as a sum of consecutive naturals, for example, 13697899 + ... + 13697904.

It is an arithmetic number, because the mean of its divisors is an integer number (27395804).

Almost surely, 2^82187409 is an apocalyptic number.

It is an amenable number.

82187409 is a deficient number, since it is larger than the sum of its proper divisors (27395807).

82187409 is a wasteful number, since it uses less digits than its factorization.

82187409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27395806.

The product of its (nonzero) digits is 32256, while the sum is 39.

The square root of 82187409 is about 9065.7271633333. The cubic root of 82187409 is about 434.7788703016.

The spelling of 82187409 in words is "eighty-two million, one hundred eighty-seven thousand, four hundred nine".