3721909 has 4 divisors (see below), whose sum is σ = 3725920. Its totient is φ = 3717900.

The previous prime is 3721901. The next prime is 3721919. The reversal of 3721909 is 9091273.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 3721909 - 2³ = 3721901 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 (3721901) 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, 184 + ... + 2734.

It is an arithmetic number, because the mean of its divisors is an integer number (931480).

Almost surely, 2^3721909 is an apocalyptic number.

It is an amenable number.

3721909 is a deficient number, since it is larger than the sum of its proper divisors (4011).

3721909 is a wasteful number, since it uses less digits than its factorization.

3721909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4010.

The product of its (nonzero) digits is 3402, while the sum is 31.

The square root of 3721909 is about 1929.2249739209. The cubic root of 3721909 is about 154.9727180565.

The spelling of 3721909 in words is "three million, seven hundred twenty-one thousand, nine hundred nine".