4020665 has 16 divisors (see below), whose sum is σ = 5394816. Its totient is φ = 2851200.

The previous prime is 4020641. The next prime is 4020671. The reversal of 4020665 is 5660204.

It is not a de Polignac number, because 4020665 - 2⁸ = 4020409 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 4020665.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1364 + ... + 3146.

It is an arithmetic number, because the mean of its divisors is an integer number (337176).

Almost surely, 2^4020665 is an apocalyptic number.

It is an amenable number.

4020665 is a deficient number, since it is larger than the sum of its proper divisors (1374151).

4020665 is a wasteful number, since it uses less digits than its factorization.

4020665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1840.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 4020665 is about 2005.1595946458. The cubic root of 4020665 is about 159.0129994778.

Adding to 4020665 its reverse (5660204), we get a palindrome (9680869).

The spelling of 4020665 in words is "four million, twenty thousand, six hundred sixty-five".