2116405 has 4 divisors (see below), whose sum is σ = 2539692. Its totient is φ = 1693120.

The previous prime is 2116403. The next prime is 2116409. The reversal of 2116405 is 5046112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 421201 + 1695204 = 649^2 + 1302^2 .

It is not a de Polignac number, because 2116405 - 2¹ = 2116403 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 (2116403) 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, 211636 + ... + 211645.

It is an arithmetic number, because the mean of its divisors is an integer number (634923).

2^2116405 is an apocalyptic number.

It is an amenable number.

2116405 is a deficient number, since it is larger than the sum of its proper divisors (423287).

2116405 is an equidigital number, since it uses as much as digits as its factorization.

2116405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423286.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 2116405 is about 1454.7869259792. The cubic root of 2116405 is about 128.3905106809.

The spelling of 2116405 in words is "two million, one hundred sixteen thousand, four hundred five".