3811721 has 8 divisors (see below), whose sum is σ = 4018560. Its totient is φ = 3608352.

The previous prime is 3811711. The next prime is 3811733. The reversal of 3811721 is 1271183.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3811721 - 2⁶ = 3811657 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is not an unprimeable number, because it can be changed into a prime (3811711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1565 + ... + 3173.

It is an arithmetic number, because the mean of its divisors is an integer number (502320).

Almost surely, 2^3811721 is an apocalyptic number.

It is an amenable number.

3811721 is a deficient number, since it is larger than the sum of its proper divisors (206839).

3811721 is a wasteful number, since it uses less digits than its factorization.

3811721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1735.

The product of its digits is 336, while the sum is 23.

The square root of 3811721 is about 1952.3629273268. The cubic root of 3811721 is about 156.2093534806.

The spelling of 3811721 in words is "three million, eight hundred eleven thousand, seven hundred twenty-one".