3909421 has 4 divisors (see below), whose sum is σ = 4115200. Its totient is φ = 3703644.

The previous prime is 3909401. The next prime is 3909427. The reversal of 3909421 is 1249093.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1249093 = 947 ⋅1319.

It is a cyclic number.

It is not a de Polignac number, because 3909421 - 2⁷ = 3909293 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 3909421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3909427) 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, 102861 + ... + 102898.

It is an arithmetic number, because the mean of its divisors is an integer number (1028800).

Almost surely, 2^3909421 is an apocalyptic number.

It is an amenable number.

3909421 is a deficient number, since it is larger than the sum of its proper divisors (205779).

3909421 is a wasteful number, since it uses less digits than its factorization.

3909421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205778.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 3909421 is about 1977.2255814651. The cubic root of 3909421 is about 157.5327352802.

The spelling of 3909421 in words is "three million, nine hundred nine thousand, four hundred twenty-one".