2118649 has 4 divisors (see below), whose sum is σ = 2281636. Its totient is φ = 1955664.

The previous prime is 2118643. The next prime is 2118661. The reversal of 2118649 is 9468112.

It is a happy number.

2118649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1281424 + 837225 = 1132^2 + 915^2 .

It is a cyclic number.

It is not a de Polignac number, because 2118649 - 2¹¹ = 2116601 is a prime.

It is a Duffinian number.

2118649 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 2118649.

It is not an unprimeable number, because it can be changed into a prime (2118643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81474 + ... + 81499.

It is an arithmetic number, because the mean of its divisors is an integer number (570409).

2^2118649 is an apocalyptic number.

It is an amenable number.

2118649 is a deficient number, since it is larger than the sum of its proper divisors (162987).

2118649 is a wasteful number, since it uses less digits than its factorization.

2118649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162986.

The product of its digits is 3456, while the sum is 31.

The square root of 2118649 is about 1455.5579686155. The cubic root of 2118649 is about 128.4358716491.

The spelling of 2118649 in words is "two million, one hundred eighteen thousand, six hundred forty-nine".