5811381 has 12 divisors (see below), whose sum is σ = 8599500. Its totient is φ = 3779520.

The previous prime is 5811373. The next prime is 5811383. The reversal of 5811381 is 1831185.

5811381 is a `hidden beast` number, since 581 + 1 + 3 + 81 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 194481 + 5616900 = 441^2 + 2370^2 .

It is not a de Polignac number, because 5811381 - 2³ = 5811373 is a prime.

It is a super-2 number, since 2×5811381² = 67544298254322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5811383) 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, 7506 + ... + 8243.

It is an arithmetic number, because the mean of its divisors is an integer number (716625).

Almost surely, 2^5811381 is an apocalyptic number.

It is an amenable number.

5811381 is a deficient number, since it is larger than the sum of its proper divisors (2788119).

5811381 is a wasteful number, since it uses less digits than its factorization.

5811381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15796 (or 15793 counting only the distinct ones).

The product of its digits is 960, while the sum is 27.

The square root of 5811381 is about 2410.6806092886. The cubic root of 5811381 is about 179.7876198838.

The spelling of 5811381 in words is "five million, eight hundred eleven thousand, three hundred eighty-one".