4025809 has 4 divisors (see below), whose sum is σ = 4164660. Its totient is φ = 3886960.

The previous prime is 4025807. The next prime is 4025837. The reversal of 4025809 is 9085204.

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 1203409 + 2822400 = 1097^2 + 1680^2 .

It is a cyclic number.

It is not a de Polignac number, because 4025809 - 2¹ = 4025807 is a prime.

It is a Duffinian number.

4025809 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (4025807) 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, 69382 + ... + 69439.

It is an arithmetic number, because the mean of its divisors is an integer number (1041165).

Almost surely, 2^4025809 is an apocalyptic number.

It is an amenable number.

4025809 is a deficient number, since it is larger than the sum of its proper divisors (138851).

4025809 is a wasteful number, since it uses less digits than its factorization.

4025809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138850.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 4025809 is about 2006.4418755598. The cubic root of 4025809 is about 159.0807838108.

The spelling of 4025809 in words is "four million, twenty-five thousand, eight hundred nine".