3994 has 4 divisors (see below), whose sum is σ = 5994. Its totient is φ = 1996.

The previous prime is 3989. The next prime is 4001. The reversal of 3994 is 4993.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 3969 + 25 = 63^2 + 5^2 .

It is an Ulam number.

It is a plaindrome in base 12.

It is a nialpdrome in base 8.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 997 + ... + 1000.

3994 is a deficient number, since it is larger than the sum of its proper divisors (2000).

3994 is a wasteful number, since it uses less digits than its factorization.

3994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1999.

The product of its digits is 972, while the sum is 25.

The square root of 3994 is about 63.1981012373. The cubic root of 3994 is about 15.8660695426.

Subtracting from 3994 its sum of digits (25), we obtain a square (3969 = 63²).

Subtracting 3994 from its reverse (4993), we obtain a palindrome (999).

It can be divided in two parts, 399 and 4, that multiplied together give a triangular number (1596 = T₅₆).

The spelling of 3994 in words is "three thousand, nine hundred ninety-four".