11820815 has 4 divisors (see below), whose sum is σ = 14184984. Its totient is φ = 9456648.

The previous prime is 11820803. The next prime is 11820839. The reversal of 11820815 is 51802811.

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

It is a cyclic number.

It is not a de Polignac number, because 11820815 - 2¹² = 11816719 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1182077 + ... + 1182086.

It is an arithmetic number, because the mean of its divisors is an integer number (3546246).

Almost surely, 2^11820815 is an apocalyptic number.

11820815 is a deficient number, since it is larger than the sum of its proper divisors (2364169).

11820815 is an equidigital number, since it uses as much as digits as its factorization.

11820815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2364168.

The product of its (nonzero) digits is 640, while the sum is 26.

The square root of 11820815 is about 3438.1412129231. The cubic root of 11820815 is about 227.7975978963.

The spelling of 11820815 in words is "eleven million, eight hundred twenty thousand, eight hundred fifteen".