2987581 has 4 divisors (see below), whose sum is σ = 3015100. Its totient is φ = 2960064.

The previous prime is 2987573. The next prime is 2987591. The reversal of 2987581 is 1857892.

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 931225 + 2056356 = 965^2 + 1434^2 .

It is a cyclic number.

It is not a de Polignac number, because 2987581 - 2³ = 2987573 is a prime.

It is a super-2 number, since 2×2987581² = 17851280463122, 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 (2987521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13596 + ... + 13813.

It is an arithmetic number, because the mean of its divisors is an integer number (753775).

2^2987581 is an apocalyptic number.

It is an amenable number.

2987581 is a deficient number, since it is larger than the sum of its proper divisors (27519).

2987581 is a wasteful number, since it uses less digits than its factorization.

2987581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27518.

The product of its digits is 40320, while the sum is 40.

The square root of 2987581 is about 1728.4620331381. The cubic root of 2987581 is about 144.0256673639.

The spelling of 2987581 in words is "two million, nine hundred eighty-seven thousand, five hundred eighty-one".