3691381 has 4 divisors (see below), whose sum is σ = 3818700. Its totient is φ = 3564064.

The previous prime is 3691367. The next prime is 3691403. The reversal of 3691381 is 1831963.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1102500 + 2588881 = 1050^2 + 1609^2 .

It is a cyclic number.

It is not a de Polignac number, because 3691381 - 2⁵ = 3691349 is a prime.

It is a super-2 number, since 2×3691381² = 27252587374322, 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 (3691351) 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, 63616 + ... + 63673.

It is an arithmetic number, because the mean of its divisors is an integer number (954675).

Almost surely, 2^3691381 is an apocalyptic number.

It is an amenable number.

3691381 is a deficient number, since it is larger than the sum of its proper divisors (127319).

3691381 is a wasteful number, since it uses less digits than its factorization.

3691381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127318.

The product of its digits is 3888, while the sum is 31.

The square root of 3691381 is about 1921.2966975457. The cubic root of 3691381 is about 154.5478463612.

The spelling of 3691381 in words is "three million, six hundred ninety-one thousand, three hundred eighty-one".