872405 has 4 divisors (see below), whose sum is σ = 1046892. Its totient is φ = 697920.

The previous prime is 872393. The next prime is 872411. The reversal of 872405 is 504278.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 504278 = 2 ⋅252139.

It can be written as a sum of positive squares in 2 ways, for example, as 320356 + 552049 = 566^2 + 743^2 .

It is not a de Polignac number, because 872405 - 2⁸ = 872149 is a prime.

It is a super-2 number, since 2×872405² = 1522180968050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 872405.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 87236 + ... + 87245.

It is an arithmetic number, because the mean of its divisors is an integer number (261723).

2⁸⁷²⁴⁰⁵ is an apocalyptic number.

It is an amenable number.

872405 is a deficient number, since it is larger than the sum of its proper divisors (174487).

872405 is a wasteful number, since it uses less digits than its factorization.

872405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174486.

The product of its (nonzero) digits is 2240, while the sum is 26.

The square root of 872405 is about 934.0262308950. The cubic root of 872405 is about 95.5519120559.

The spelling of 872405 in words is "eight hundred seventy-two thousand, four hundred five".