12281581 has 12 divisors (see below), whose sum is σ = 13964412. Its totient is φ = 10736064.

The previous prime is 12281573. The next prime is 12281597. The reversal of 12281581 is 18518221.

It can be written as a sum of positive squares in 2 ways, for example, as 7590025 + 4691556 = 2755^2 + 2166^2 .

It is not a de Polignac number, because 12281581 - 2³ = 12281573 is a prime.

It is a super-2 number, since 2×12281581² = 301674463719122, 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 (12281881) 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, 3385 + ... + 6001.

It is an arithmetic number, because the mean of its divisors is an integer number (1163701).

Almost surely, 2^12281581 is an apocalyptic number.

It is an amenable number.

12281581 is a deficient number, since it is larger than the sum of its proper divisors (1682831).

12281581 is a wasteful number, since it uses less digits than its factorization.

12281581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2668 (or 2649 counting only the distinct ones).

The product of its digits is 1280, while the sum is 28.

The square root of 12281581 is about 3504.5086674169. The cubic root of 12281581 is about 230.7197428269.

It can be divided in two parts, 1228 and 1581, that added together give a square (2809 = 53²).

The spelling of 12281581 in words is "twelve million, two hundred eighty-one thousand, five hundred eighty-one".