3666861 has 12 divisors (see below), whose sum is σ = 5778240. Its totient is φ = 2222280.

The previous prime is 3666853. The next prime is 3666877. The reversal of 3666861 is 1686663.

It is not a de Polignac number, because 3666861 - 2³ = 3666853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3666841) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18421 + ... + 18618.

It is an arithmetic number, because the mean of its divisors is an integer number (481520).

Almost surely, 2^3666861 is an apocalyptic number.

It is an amenable number.

3666861 is a deficient number, since it is larger than the sum of its proper divisors (2111379).

3666861 is a wasteful number, since it uses less digits than its factorization.

3666861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37056 (or 37053 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 3666861 is about 1914.9049584771. The cubic root of 3666861 is about 154.2048911629.

It can be divided in two parts, 366 and 6861, that added together give a palindrome (7227).

The spelling of 3666861 in words is "three million, six hundred sixty-six thousand, eight hundred sixty-one".