3918321 has 32 divisors (see below), whose sum is σ = 6451200. Its totient is φ = 2330640.

The previous prime is 3918311. The next prime is 3918323. The reversal of 3918321 is 1238193.

3918321 is nontrivially palindromic in base 8.

It is not a de Polignac number, because 3918321 - 2⁷ = 3918193 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (3918323) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23380 + ... + 23546.

It is an arithmetic number, because the mean of its divisors is an integer number (201600).

Almost surely, 2^3918321 is an apocalyptic number.

It is an amenable number.

3918321 is a deficient number, since it is larger than the sum of its proper divisors (2532879).

3918321 is a wasteful number, since it uses less digits than its factorization.

3918321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 260 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 3918321 is about 1979.4749303793. The cubic root of 3918321 is about 157.6521884974.

It can be divided in two parts, 39183 and 21, that added together give a square (39204 = 198²).

The spelling of 3918321 in words is "three million, nine hundred eighteen thousand, three hundred twenty-one".