3839721 has 4 divisors (see below), whose sum is σ = 5119632. Its totient is φ = 2559812.

The previous prime is 3839713. The next prime is 3839747. The reversal of 3839721 is 1279383.

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 3839721 - 2³ = 3839713 is a prime.

It is a D-number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (3839701) 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 3 ways as a sum of consecutive naturals, for example, 639951 + ... + 639956.

It is an arithmetic number, because the mean of its divisors is an integer number (1279908).

Almost surely, 2^3839721 is an apocalyptic number.

It is an amenable number.

3839721 is a deficient number, since it is larger than the sum of its proper divisors (1279911).

3839721 is a wasteful number, since it uses less digits than its factorization.

3839721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1279910.

The product of its digits is 9072, while the sum is 33.

The square root of 3839721 is about 1959.5206046378. The cubic root of 3839721 is about 156.5909130269.

It can be divided in two parts, 3839 and 721, that added together give a triangular number (4560 = T₉₅).

The spelling of 3839721 in words is "three million, eight hundred thirty-nine thousand, seven hundred twenty-one".