2187815 has 16 divisors (see below), whose sum is σ = 3177792. Its totient is φ = 1411584.

The previous prime is 2187811. The next prime is 2187817. The reversal of 2187815 is 5187812.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2187815 - 2² = 2187811 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 (2187811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1244 + ... + 2433.

It is an arithmetic number, because the mean of its divisors is an integer number (198612).

2^2187815 is an apocalyptic number.

2187815 is a deficient number, since it is larger than the sum of its proper divisors (989977).

2187815 is a wasteful number, since it uses less digits than its factorization.

2187815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3706.

The product of its digits is 4480, while the sum is 32.

The square root of 2187815 is about 1479.1264313777. The cubic root of 2187815 is about 129.8185832401.

The spelling of 2187815 in words is "two million, one hundred eighty-seven thousand, eight hundred fifteen".