4187989 has 6 divisors (see below), whose sum is σ = 4535106. Its totient is φ = 3865680.

The previous prime is 4187987. The next prime is 4188011. The reversal of 4187989 is 9897814.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 18225 + 4169764 = 135^2 + 2042^2 .

It is not a de Polignac number, because 4187989 - 2¹ = 4187987 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4187983) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12222 + ... + 12559.

It is an arithmetic number, because the mean of its divisors is an integer number (755851).

Almost surely, 2^4187989 is an apocalyptic number.

It is an amenable number.

4187989 is a deficient number, since it is larger than the sum of its proper divisors (347117).

4187989 is a wasteful number, since it uses less digits than its factorization.

4187989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24807 (or 24794 counting only the distinct ones).

The product of its digits is 145152, while the sum is 46.

The square root of 4187989 is about 2046.4576711967. The cubic root of 4187989 is about 161.1889170320.

The spelling of 4187989 in words is "four million, one hundred eighty-seven thousand, nine hundred eighty-nine".