4278665 has 4 divisors (see below), whose sum is σ = 5134404. Its totient is φ = 3422928.

The previous prime is 4278661. The next prime is 4278671. The reversal of 4278665 is 5668724.

It is a happy number.

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 1106704 + 3171961 = 1052^2 + 1781^2 .

It is a cyclic number.

It is not a de Polignac number, because 4278665 - 2² = 4278661 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 (4278661) 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, 427862 + ... + 427871.

It is an arithmetic number, because the mean of its divisors is an integer number (1283601).

Almost surely, 2^4278665 is an apocalyptic number.

It is an amenable number.

4278665 is a deficient number, since it is larger than the sum of its proper divisors (855739).

4278665 is an equidigital number, since it uses as much as digits as its factorization.

4278665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 855738.

The product of its digits is 80640, while the sum is 38.

The square root of 4278665 is about 2068.4934130908. The cubic root of 4278665 is about 162.3439448566.

The spelling of 4278665 in words is "four million, two hundred seventy-eight thousand, six hundred sixty-five".