2221605 has 12 divisors (see below), whose sum is σ = 3850860. Its totient is φ = 1184832.

The previous prime is 2221589. The next prime is 2221631. The reversal of 2221605 is 5061222.

It can be written as a sum of positive squares in 2 ways, for example, as 580644 + 1640961 = 762^2 + 1281^2 .

It is not a de Polignac number, because 2221605 - 2⁴ = 2221589 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24640 + ... + 24729.

It is an arithmetic number, because the mean of its divisors is an integer number (320905).

2^2221605 is an apocalyptic number.

It is an amenable number.

2221605 is a deficient number, since it is larger than the sum of its proper divisors (1629255).

2221605 is a wasteful number, since it uses less digits than its factorization.

2221605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49380 (or 49377 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 2221605 is about 1490.5049479958. The cubic root of 2221605 is about 130.4835052037.

Adding to 2221605 its reverse (5061222), we get a palindrome (7282827).

The spelling of 2221605 in words is "two million, two hundred twenty-one thousand, six hundred five".