3664021 has 4 divisors (see below), whose sum is σ = 3668652. Its totient is φ = 3659392.

The previous prime is 3664013. The next prime is 3664033. The reversal of 3664021 is 1204663.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1204663 = 761 ⋅1583.

It can be written as a sum of positive squares in 2 ways, for example, as 12100 + 3651921 = 110^2 + 1911^2 .

It is a cyclic number.

It is not a de Polignac number, because 3664021 - 2³ = 3664013 is a prime.

It is a Smith number, since the sum of its digits (22) 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 a junction number, because it is equal to n+sod(n) for n = 3663983 and 3664001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3664081) 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 3 ways as a sum of consecutive naturals, for example, 796 + ... + 2821.

It is an arithmetic number, because the mean of its divisors is an integer number (917163).

Almost surely, 2^3664021 is an apocalyptic number.

It is an amenable number.

3664021 is a deficient number, since it is larger than the sum of its proper divisors (4631).

3664021 is a wasteful number, since it uses less digits than its factorization.

3664021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4630.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 3664021 is about 1914.1632636742. The cubic root of 3664021 is about 154.1650700914.

Adding to 3664021 its reverse (1204663), we get a palindrome (4868684).

The spelling of 3664021 in words is "three million, six hundred sixty-four thousand, twenty-one".