3687981 has 32 divisors (see below), whose sum is σ = 5778432. Its totient is φ = 2069760.

The previous prime is 3687979. The next prime is 3687989. The reversal of 3687981 is 1897863.

It is not a de Polignac number, because 3687981 - 2¹ = 3687979 is a prime.

It is a super-2 number, since 2×3687981² = 27202407712722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3687989) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32581 + ... + 32693.

It is an arithmetic number, because the mean of its divisors is an integer number (180576).

Almost surely, 2^3687981 is an apocalyptic number.

It is an amenable number.

3687981 is a deficient number, since it is larger than the sum of its proper divisors (2090451).

3687981 is a wasteful number, since it uses less digits than its factorization.

3687981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193.

The product of its digits is 72576, while the sum is 42.

The square root of 3687981 is about 1920.4116746156. The cubic root of 3687981 is about 154.5003822741.

The spelling of 3687981 in words is "three million, six hundred eighty-seven thousand, nine hundred eighty-one".