2215811 has 4 divisors (see below), whose sum is σ = 2386272. Its totient is φ = 2045352.

The previous prime is 2215793. The next prime is 2215823. The reversal of 2215811 is 1185122.

It is a happy number.

2215811 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1185122 = 2 ⋅592561.

It is a cyclic number.

It is not a de Polignac number, because 2215811 - 2¹⁴ = 2199427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2215111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85211 + ... + 85236.

It is an arithmetic number, because the mean of its divisors is an integer number (596568).

2^2215811 is an apocalyptic number.

2215811 is a deficient number, since it is larger than the sum of its proper divisors (170461).

2215811 is a wasteful number, since it uses less digits than its factorization.

2215811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170460.

The product of its digits is 160, while the sum is 20.

The square root of 2215811 is about 1488.5600424571. The cubic root of 2215811 is about 130.3699717262.

The spelling of 2215811 in words is "two million, two hundred fifteen thousand, eight hundred eleven".