5781681 has 12 divisors (see below), whose sum is σ = 8791120. Its totient is φ = 3651480.

The previous prime is 5781661. The next prime is 5781689. The reversal of 5781681 is 1861875.

5781681 is a `hidden beast` number, since 578 + 1 + 6 + 81 = 666.

It is not a de Polignac number, because 5781681 - 2⁷ = 5781553 is a prime.

It is a super-2 number, since 2×5781681² = 66855670371522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5781689) 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, 16735 + ... + 17076.

Almost surely, 2^5781681 is an apocalyptic number.

It is an amenable number.

5781681 is a deficient number, since it is larger than the sum of its proper divisors (3009439).

5781681 is a wasteful number, since it uses less digits than its factorization.

5781681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33836 (or 33833 counting only the distinct ones).

The product of its digits is 13440, while the sum is 36.

The square root of 5781681 is about 2404.5126325308. The cubic root of 5781681 is about 179.4808187592.

The spelling of 5781681 in words is "five million, seven hundred eighty-one thousand, six hundred eighty-one".