4021959 has 4 divisors (see below), whose sum is σ = 5362616. Its totient is φ = 2681304.

The previous prime is 4021949. The next prime is 4021961. The reversal of 4021959 is 9591204.

It is a happy number.

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

It is not a de Polignac number, because 4021959 - 2⁹ = 4021447 is a prime.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4021949) 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, 670324 + ... + 670329.

It is an arithmetic number, because the mean of its divisors is an integer number (1340654).

Almost surely, 2^4021959 is an apocalyptic number.

4021959 is a deficient number, since it is larger than the sum of its proper divisors (1340657).

4021959 is a wasteful number, since it uses less digits than its factorization.

4021959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1340656.

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 4021959 is about 2005.4822362714. The cubic root of 4021959 is about 159.0300564199.

It can be divided in two parts, 402195 and 9, that added together give a palindrome (402204).

The spelling of 4021959 in words is "four million, twenty-one thousand, nine hundred fifty-nine".