3989945 has 8 divisors (see below), whose sum is σ = 4832520. Its totient is φ = 3162240.

The previous prime is 3989941. The next prime is 3989957. The reversal of 3989945 is 5499893.

It can be written as a sum of positive squares in 4 ways, for example, as 5929 + 3984016 = 77^2 + 1996^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 3989945 - 2² = 3989941 is a prime.

It is a super-2 number, since 2×3989945² = 31839322206050, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 3989945.

It is not an unprimeable number, because it can be changed into a prime (3989941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3116 + ... + 4205.

It is an arithmetic number, because the mean of its divisors is an integer number (604065).

Almost surely, 2^3989945 is an apocalyptic number.

It is an amenable number.

3989945 is a deficient number, since it is larger than the sum of its proper divisors (842575).

3989945 is a wasteful number, since it uses less digits than its factorization.

3989945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7435.

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

The square root of 3989945 is about 1997.4846682766. The cubic root of 3989945 is about 158.6069826090.

The spelling of 3989945 in words is "three million, nine hundred eighty-nine thousand, nine hundred forty-five".