2217905 has 16 divisors (see below), whose sum is σ = 2857680. Its totient is φ = 1646592.

The previous prime is 2217881. The next prime is 2217907. The reversal of 2217905 is 5097122.

It can be written as a sum of positive squares in 8 ways, for example, as 97969 + 2119936 = 313^2 + 1456^2 .

It is a cyclic number.

It is not a de Polignac number, because 2217905 - 2¹⁶ = 2152369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2217907) 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, 8111 + ... + 8379.

It is an arithmetic number, because the mean of its divisors is an integer number (178605).

2^2217905 is an apocalyptic number.

It is an amenable number.

2217905 is a deficient number, since it is larger than the sum of its proper divisors (639775).

2217905 is a wasteful number, since it uses less digits than its factorization.

2217905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 2217905 is about 1489.2632406663. The cubic root of 2217905 is about 130.4110264868.

The spelling of 2217905 in words is "two million, two hundred seventeen thousand, nine hundred five".