8123405 has 4 divisors (see below), whose sum is σ = 9748092. Its totient is φ = 6498720.

The previous prime is 8123389. The next prime is 8123407. The reversal of 8123405 is 5043218.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5043218 = 2 ⋅2521609.

It can be written as a sum of positive squares in 2 ways, for example, as 1503076 + 6620329 = 1226^2 + 2573^2 .

It is not a de Polignac number, because 8123405 - 2⁴ = 8123389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8123407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 812336 + ... + 812345.

It is an arithmetic number, because the mean of its divisors is an integer number (2437023).

Almost surely, 2^8123405 is an apocalyptic number.

It is an amenable number.

8123405 is a deficient number, since it is larger than the sum of its proper divisors (1624687).

8123405 is a wasteful number, since it uses less digits than its factorization.

8123405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1624686.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 8123405 is about 2850.1587675075. The cubic root of 8123405 is about 201.0231320786.

The spelling of 8123405 in words is "eight million, one hundred twenty-three thousand, four hundred five".