2187813 has 4 divisors (see below), whose sum is σ = 2917088. Its totient is φ = 1458540.

The previous prime is 2187811. The next prime is 2187817. The reversal of 2187813 is 3187812.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2187813 - 2¹ = 2187811 is a prime.

It is a D-number.

It is a Duffinian number.

2187813 is a lucky 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 3 ways as a sum of consecutive naturals, for example, 364633 + ... + 364638.

It is an arithmetic number, because the mean of its divisors is an integer number (729272).

2^2187813 is an apocalyptic number.

It is an amenable number.

2187813 is a deficient number, since it is larger than the sum of its proper divisors (729275).

2187813 is an equidigital number, since it uses as much as digits as its factorization.

2187813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 729274.

The product of its digits is 2688, while the sum is 30.

The square root of 2187813 is about 1479.1257553028. The cubic root of 2187813 is about 129.8185436821.

Subtracting 2187813 from its reverse (3187812), we obtain a palindrome (999999).

The spelling of 2187813 in words is "two million, one hundred eighty-seven thousand, eight hundred thirteen".