3621805 has 8 divisors (see below), whose sum is σ = 4741344. Its totient is φ = 2634000.

The previous prime is 3621803. The next prime is 3621851. The reversal of 3621805 is 5081263.

It is a happy number.

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

It is not a de Polignac number, because 3621805 - 2¹ = 3621803 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3621805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3621803) 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, 32871 + ... + 32980.

It is an arithmetic number, because the mean of its divisors is an integer number (592668).

Almost surely, 2^3621805 is an apocalyptic number.

It is an amenable number.

3621805 is a deficient number, since it is larger than the sum of its proper divisors (1119539).

3621805 is a wasteful number, since it uses less digits than its factorization.

3621805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65867.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 3621805 is about 1903.1040433986. The cubic root of 3621805 is about 153.5706967438.

It can be divided in two parts, 3621 and 805, that multiplied together give a triangular number (2914905 = T₂₄₁₄).

The spelling of 3621805 in words is "three million, six hundred twenty-one thousand, eight hundred five".