3853721 has 4 divisors (see below), whose sum is σ = 3857700. Its totient is φ = 3849744.

The previous prime is 3853711. The next prime is 3853727. The reversal of 3853721 is 1273583.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1273583 = 41 ⋅31063.

It can be written as a sum of positive squares in 2 ways, for example, as 2676496 + 1177225 = 1636^2 + 1085^2 .

It is a cyclic number.

It is not a de Polignac number, because 3853721 - 2¹⁰ = 3852697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3853727) 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, 515 + ... + 2823.

It is an arithmetic number, because the mean of its divisors is an integer number (964425).

Almost surely, 2^3853721 is an apocalyptic number.

It is an amenable number.

3853721 is a deficient number, since it is larger than the sum of its proper divisors (3979).

3853721 is a wasteful number, since it uses less digits than its factorization.

3853721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3978.

The product of its digits is 5040, while the sum is 29.

The square root of 3853721 is about 1963.0896566382. The cubic root of 3853721 is about 156.7809974759.

The spelling of 3853721 in words is "three million, eight hundred fifty-three thousand, seven hundred twenty-one".