2065581 has 20 divisors (see below), whose sum is σ = 3527392. Its totient is φ = 1180008.

The previous prime is 2065579. The next prime is 2065597. The reversal of 2065581 is 1855602.

2065581 is a `hidden beast` number, since 2 + 0 + 655 + 8 + 1 = 666.

It is not a de Polignac number, because 2065581 - 2¹ = 2065579 is a prime.

It is a super-2 number, since 2×2065581² = 8533249735122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2065501) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1255 + ... + 2388.

2^2065581 is an apocalyptic number.

2065581 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2065581 is a deficient number, since it is larger than the sum of its proper divisors (1461811).

2065581 is an equidigital number, since it uses as much as digits as its factorization.

2065581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3662 (or 3653 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

The square root of 2065581 is about 1437.2129278572. The cubic root of 2065581 is about 127.3544359520.

It can be divided in two parts, 20655 and 81, that added together give a 4-th power (20736 = 12⁴).

The spelling of 2065581 in words is "two million, sixty-five thousand, five hundred eighty-one".