3920621 has 4 divisors (see below), whose sum is σ = 3956700. Its totient is φ = 3884544.

The previous prime is 3920561. The next prime is 3920629. The reversal of 3920621 is 1260293.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3258025 + 662596 = 1805^2 + 814^2 .

It is a cyclic number.

It is not a de Polignac number, because 3920621 - 2¹⁸ = 3658477 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3920629) 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, 17876 + ... + 18093.

It is an arithmetic number, because the mean of its divisors is an integer number (989175).

Almost surely, 2^3920621 is an apocalyptic number.

It is an amenable number.

3920621 is a deficient number, since it is larger than the sum of its proper divisors (36079).

3920621 is a wasteful number, since it uses less digits than its factorization.

3920621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36078.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 3920621 is about 1980.0558072943. The cubic root of 3920621 is about 157.6830290122.

The spelling of 3920621 in words is "three million, nine hundred twenty thousand, six hundred twenty-one".