3641821 has 4 divisors (see below), whose sum is σ = 3688000. Its totient is φ = 3595644.

The previous prime is 3641819. The next prime is 3641831. The reversal of 3641821 is 1281463.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 3641821 - 2¹ = 3641819 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3641801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22971 + ... + 23128.

It is an arithmetic number, because the mean of its divisors is an integer number (922000).

Almost surely, 2^3641821 is an apocalyptic number.

It is an amenable number.

3641821 is a deficient number, since it is larger than the sum of its proper divisors (46179).

3641821 is an equidigital number, since it uses as much as digits as its factorization.

3641821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46178.

The product of its digits is 1152, while the sum is 25.

The square root of 3641821 is about 1908.3555748340. The cubic root of 3641821 is about 153.8530813355.

The spelling of 3641821 in words is "three million, six hundred forty-one thousand, eight hundred twenty-one".