4278721 has 4 divisors (see below), whose sum is σ = 4306132. Its totient is φ = 4251312.

The previous prime is 4278709. The next prime is 4278731. The reversal of 4278721 is 1278724.

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 1718721 + 2560000 = 1311^2 + 1600^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4278721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4278731) 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, 13470 + ... + 13783.

It is an arithmetic number, because the mean of its divisors is an integer number (1076533).

Almost surely, 2^4278721 is an apocalyptic number.

It is an amenable number.

4278721 is a deficient number, since it is larger than the sum of its proper divisors (27411).

4278721 is a wasteful number, since it uses less digits than its factorization.

4278721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27410.

The product of its digits is 6272, while the sum is 31.

The square root of 4278721 is about 2068.5069494686. The cubic root of 4278721 is about 162.3446531166.

The spelling of 4278721 in words is "four million, two hundred seventy-eight thousand, seven hundred twenty-one".