3686981 has 4 divisors (see below), whose sum is σ = 3691500. Its totient is φ = 3682464.

The previous prime is 3686971. The next prime is 3686983. The reversal of 3686981 is 1896863.

It is a happy number.

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: 1896863 = 179 ⋅10597.

It can be written as a sum of positive squares in 2 ways, for example, as 592900 + 3094081 = 770^2 + 1759^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3686981 is a prime.

It is a super-2 number, since 2×3686981² = 27187657788722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3686983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 656 + ... + 2793.

It is an arithmetic number, because the mean of its divisors is an integer number (922875).

Almost surely, 2^3686981 is an apocalyptic number.

It is an amenable number.

3686981 is a deficient number, since it is larger than the sum of its proper divisors (4519).

3686981 is a wasteful number, since it uses less digits than its factorization.

3686981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4518.

The product of its digits is 62208, while the sum is 41.

The square root of 3686981 is about 1920.1512961223. The cubic root of 3686981 is about 154.4864166970.

The spelling of 3686981 in words is "three million, six hundred eighty-six thousand, nine hundred eighty-one".