5581681 has 4 divisors (see below), whose sum is σ = 6379072. Its totient is φ = 4784292.

The previous prime is 5581679. The next prime is 5581691. The reversal of 5581681 is 1861855.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1861855 = 5 ⋅372371.

It is a cyclic number.

It is not a de Polignac number, because 5581681 - 2¹ = 5581679 is a prime.

It is a super-2 number, since 2×5581681² = 62310325571522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (5581651) 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, 398685 + ... + 398698.

It is an arithmetic number, because the mean of its divisors is an integer number (1594768).

Almost surely, 2^5581681 is an apocalyptic number.

It is an amenable number.

5581681 is a deficient number, since it is larger than the sum of its proper divisors (797391).

5581681 is an equidigital number, since it uses as much as digits as its factorization.

5581681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 797390.

The product of its digits is 9600, while the sum is 34.

The square root of 5581681 is about 2362.5581474326. The cubic root of 5581681 is about 177.3869517545.

The spelling of 5581681 in words is "five million, five hundred eighty-one thousand, six hundred eighty-one".