3951985 has 4 divisors (see below), whose sum is σ = 4742388. Its totient is φ = 3161584.

The previous prime is 3951977. The next prime is 3951989. The reversal of 3951985 is 5891593.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5891593 = 167 ⋅35279.

It can be written as a sum of positive squares in 2 ways, for example, as 913936 + 3038049 = 956^2 + 1743^2 .

It is a cyclic number.

It is not a de Polignac number, because 3951985 - 2³ = 3951977 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3951989) 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, 395194 + ... + 395203.

It is an arithmetic number, because the mean of its divisors is an integer number (1185597).

Almost surely, 2^3951985 is an apocalyptic number.

It is an amenable number.

3951985 is a deficient number, since it is larger than the sum of its proper divisors (790403).

3951985 is an equidigital number, since it uses as much as digits as its factorization.

3951985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 790402.

The product of its digits is 48600, while the sum is 40.

The square root of 3951985 is about 1987.9600096581. The cubic root of 3951985 is about 158.1023878366.

The spelling of 3951985 in words is "three million, nine hundred fifty-one thousand, nine hundred eighty-five".