11987405 has 4 divisors (see below), whose sum is σ = 14384892. Its totient is φ = 9589920.

The previous prime is 11987401. The next prime is 11987407. The reversal of 11987405 is 50478911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50478911 = 7 ⋅7211273.

It can be written as a sum of positive squares in 2 ways, for example, as 7382089 + 4605316 = 2717^2 + 2146^2 .

It is not a de Polignac number, because 11987405 - 2² = 11987401 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 (11987401) 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, 1198736 + ... + 1198745.

It is an arithmetic number, because the mean of its divisors is an integer number (3596223).

Almost surely, 2^11987405 is an apocalyptic number.

It is an amenable number.

11987405 is a deficient number, since it is larger than the sum of its proper divisors (2397487).

11987405 is an equidigital number, since it uses as much as digits as its factorization.

11987405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2397486.

The product of its (nonzero) digits is 10080, while the sum is 35.

The square root of 11987405 is about 3462.2832062095. The cubic root of 11987405 is about 228.8627222717.

The spelling of 11987405 in words is "eleven million, nine hundred eighty-seven thousand, four hundred five".