2217661 has 4 divisors (see below), whose sum is σ = 2334400. Its totient is φ = 2100924.

The previous prime is 2217643. The next prime is 2217671. The reversal of 2217661 is 1667122.

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 a cyclic number.

It is not a de Polignac number, because 2217661 - 2¹⁵ = 2184893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2217641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58341 + ... + 58378.

It is an arithmetic number, because the mean of its divisors is an integer number (583600).

2^2217661 is an apocalyptic number.

It is an amenable number.

2217661 is a deficient number, since it is larger than the sum of its proper divisors (116739).

2217661 is a wasteful number, since it uses less digits than its factorization.

2217661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116738.

The product of its digits is 1008, while the sum is 25.

The square root of 2217661 is about 1489.1813187117. The cubic root of 2217661 is about 130.4062439769.

The spelling of 2217661 in words is "two million, two hundred seventeen thousand, six hundred sixty-one".