3642821 has 8 divisors (see below), whose sum is σ = 4483584. Its totient is φ = 2882160.

The previous prime is 3642817. The next prime is 3642823. The reversal of 3642821 is 1282463.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3642821 - 2² = 3642817 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3642823) 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 7 ways as a sum of consecutive naturals, for example, 19925 + ... + 20106.

It is an arithmetic number, because the mean of its divisors is an integer number (560448).

Almost surely, 2^3642821 is an apocalyptic number.

It is an amenable number.

3642821 is a deficient number, since it is larger than the sum of its proper divisors (840763).

3642821 is a wasteful number, since it uses less digits than its factorization.

3642821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40051.

The product of its digits is 2304, while the sum is 26.

The square root of 3642821 is about 1908.6175625305. The cubic root of 3642821 is about 153.8671621119.

The spelling of 3642821 in words is "three million, six hundred forty-two thousand, eight hundred twenty-one".