2087581 has 4 divisors (see below), whose sum is σ = 2116252. Its totient is φ = 2058912.

The previous prime is 2087563. The next prime is 2087593. The reversal of 2087581 is 1857802.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1779556 + 308025 = 1334^2 + 555^2 .

It is a cyclic number.

It is not a de Polignac number, because 2087581 - 2⁷ = 2087453 is a prime.

It is a super-2 number, since 2×2087581² = 8715988863122, 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 (2087531) 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, 14226 + ... + 14371.

It is an arithmetic number, because the mean of its divisors is an integer number (529063).

2^2087581 is an apocalyptic number.

It is an amenable number.

2087581 is a deficient number, since it is larger than the sum of its proper divisors (28671).

2087581 is an equidigital number, since it uses as much as digits as its factorization.

2087581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28670.

The product of its (nonzero) digits is 4480, while the sum is 31.

The square root of 2087581 is about 1444.8463586140. The cubic root of 2087581 is about 127.8049805278.

The spelling of 2087581 in words is "two million, eighty-seven thousand, five hundred eighty-one".