3868821 has 12 divisors (see below), whose sum is σ = 6096480. Its totient is φ = 2344680.

The previous prime is 3868817. The next prime is 3868847. The reversal of 3868821 is 1288683.

It is not a de Polignac number, because 3868821 - 2² = 3868817 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

3868821 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3868811) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19441 + ... + 19638.

It is an arithmetic number, because the mean of its divisors is an integer number (508040).

Almost surely, 2^3868821 is an apocalyptic number.

It is an amenable number.

3868821 is a deficient number, since it is larger than the sum of its proper divisors (2227659).

3868821 is a wasteful number, since it uses less digits than its factorization.

3868821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39096 (or 39093 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 3868821 is about 1966.9318747735. The cubic root of 3868821 is about 156.9855017918.

The spelling of 3868821 in words is "three million, eight hundred sixty-eight thousand, eight hundred twenty-one".