2143649 has 4 divisors (see below), whose sum is σ = 2269764. Its totient is φ = 2017536.

The previous prime is 2143627. The next prime is 2143667. The reversal of 2143649 is 9463412.

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 1254400 + 889249 = 1120^2 + 943^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2143649 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2148649) 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, 63032 + ... + 63065.

It is an arithmetic number, because the mean of its divisors is an integer number (567441).

2^2143649 is an apocalyptic number.

It is an amenable number.

2143649 is a deficient number, since it is larger than the sum of its proper divisors (126115).

2143649 is a wasteful number, since it uses less digits than its factorization.

2143649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126114.

The product of its digits is 5184, while the sum is 29.

The square root of 2143649 is about 1464.1205551456. The cubic root of 2143649 is about 128.9390774564.

The spelling of 2143649 in words is "two million, one hundred forty-three thousand, six hundred forty-nine".