3945989 has 4 divisors (see below), whose sum is σ = 4178124. Its totient is φ = 3713856.

The previous prime is 3945983. The next prime is 3946027. The reversal of 3945989 is 9895493.

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 2464900 + 1481089 = 1570^2 + 1217^2 .

It is a cyclic number.

It is not a de Polignac number, because 3945989 - 2⁴ = 3945973 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3945983) 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, 116042 + ... + 116075.

It is an arithmetic number, because the mean of its divisors is an integer number (1044531).

Almost surely, 2^3945989 is an apocalyptic number.

It is an amenable number.

3945989 is a deficient number, since it is larger than the sum of its proper divisors (232135).

3945989 is a wasteful number, since it uses less digits than its factorization.

3945989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232134.

The product of its digits is 349920, while the sum is 47.

The square root of 3945989 is about 1986.4513585789. The cubic root of 3945989 is about 158.0223890721.

The spelling of 3945989 in words is "three million, nine hundred forty-five thousand, nine hundred eighty-nine".