2215945 has 4 divisors (see below), whose sum is σ = 2659140. Its totient is φ = 1772752.

The previous prime is 2215943. The next prime is 2215949. The reversal of 2215945 is 5495122.

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

It can be written as a sum of positive squares in 2 ways, for example, as 968256 + 1247689 = 984^2 + 1117^2 .

It is a cyclic number.

It is not a de Polignac number, because 2215945 - 2¹ = 2215943 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2215943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 221590 + ... + 221599.

It is an arithmetic number, because the mean of its divisors is an integer number (664785).

2^2215945 is an apocalyptic number.

It is an amenable number.

2215945 is a deficient number, since it is larger than the sum of its proper divisors (443195).

2215945 is an equidigital number, since it uses as much as digits as its factorization.

2215945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443194.

The product of its digits is 3600, while the sum is 28.

The square root of 2215945 is about 1488.6050517179. The cubic root of 2215945 is about 130.3725996916.

It can be divided in two parts, 2215 and 945, that added together give a triangular number (3160 = T₇₉).

The spelling of 2215945 in words is "two million, two hundred fifteen thousand, nine hundred forty-five".