3866721 has 16 divisors (see below), whose sum is σ = 5334336. Its totient is φ = 2490176.

The previous prime is 3866719. The next prime is 3866741. The reversal of 3866721 is 1276683.

It is a cyclic number.

It is not a de Polignac number, because 3866721 - 2¹ = 3866719 is a prime.

Its product of digits (12096) is a multiple of the sum of its prime divisors (432).

It is not an unprimeable number, because it can be changed into a prime (3866741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13051 + ... + 13343.

It is an arithmetic number, because the mean of its divisors is an integer number (333396).

Almost surely, 2^3866721 is an apocalyptic number.

It is an amenable number.

3866721 is a deficient number, since it is larger than the sum of its proper divisors (1467615).

3866721 is a wasteful number, since it uses less digits than its factorization.

3866721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432.

The product of its digits is 12096, while the sum is 33.

The square root of 3866721 is about 1966.3979759957. The cubic root of 3866721 is about 156.9570926873.

The spelling of 3866721 in words is "three million, eight hundred sixty-six thousand, seven hundred twenty-one".