2218657 has 4 divisors (see below), whose sum is σ = 2535616. Its totient is φ = 1901700.

The previous prime is 2218621. The next prime is 2218663. The reversal of 2218657 is 7568122.

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 2218657 - 2¹¹ = 2216609 is a prime.

It is an Ulam number.

It is a d-powerful number, because it can be written as 2 + 2²¹ + 1 + 8³ + 6³ + 5⁵ + 7⁶ .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2218607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 158469 + ... + 158482.

It is an arithmetic number, because the mean of its divisors is an integer number (633904).

2^2218657 is an apocalyptic number.

It is an amenable number.

2218657 is a deficient number, since it is larger than the sum of its proper divisors (316959).

2218657 is an equidigital number, since it uses as much as digits as its factorization.

2218657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316958.

The product of its digits is 6720, while the sum is 31.

The square root of 2218657 is about 1489.5156931030. The cubic root of 2218657 is about 130.4257638193.

The spelling of 2218657 in words is "two million, two hundred eighteen thousand, six hundred fifty-seven".