2281681 has 4 divisors (see below), whose sum is σ = 2296372. Its totient is φ = 2266992.

The previous prime is 2281673. The next prime is 2281687. The reversal of 2281681 is 1861822.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1861822 = 2 ⋅930911.

It can be written as a sum of positive squares in 2 ways, for example, as 982081 + 1299600 = 991^2 + 1140^2 .

It is a cyclic number.

It is not a de Polignac number, because 2281681 - 2³ = 2281673 is a prime.

It is a super-2 number, since 2×2281681² = 10412136371522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2281687) 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, 7110 + ... + 7423.

It is an arithmetic number, because the mean of its divisors is an integer number (574093).

2^2281681 is an apocalyptic number.

It is an amenable number.

2281681 is a deficient number, since it is larger than the sum of its proper divisors (14691).

2281681 is a wasteful number, since it uses less digits than its factorization.

2281681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14690.

The product of its digits is 1536, while the sum is 28.

The square root of 2281681 is about 1510.5234192160. The cubic root of 2281681 is about 131.6492255557.

The spelling of 2281681 in words is "two million, two hundred eighty-one thousand, six hundred eighty-one".