2216639 has 4 divisors (see below), whose sum is σ = 2220840. Its totient is φ = 2212440.

The previous prime is 2216629. The next prime is 2216653. The reversal of 2216639 is 9366122.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2216639 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 (2216609) 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, 1172 + ... + 2409.

It is an arithmetic number, because the mean of its divisors is an integer number (555210).

2^2216639 is an apocalyptic number.

2216639 is a deficient number, since it is larger than the sum of its proper divisors (4201).

2216639 is an equidigital number, since it uses as much as digits as its factorization.

2216639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4200.

The product of its digits is 3888, while the sum is 29.

The square root of 2216639 is about 1488.8381376093. The cubic root of 2216639 is about 130.3862085042.

It can be divided in two parts, 22 and 16639, that added together give a palindrome (16661).

The spelling of 2216639 in words is "two million, two hundred sixteen thousand, six hundred thirty-nine".