2018581 has 2 divisors, whose sum is σ = 2018582. Its totient is φ = 2018580.

The previous prime is 2018573. The next prime is 2018591. The reversal of 2018581 is 1858102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1575025 + 443556 = 1255^2 + 666^2 .

It is a cyclic number.

It is not a de Polignac number, because 2018581 - 2³ = 2018573 is a prime.

It is a super-2 number, since 2×2018581² = 8149338507122, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2018531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1009290 + 1009291.

It is an arithmetic number, because the mean of its divisors is an integer number (1009291).

2^2018581 is an apocalyptic number.

It is an amenable number.

2018581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2018581 is an equidigital number, since it uses as much as digits as its factorization.

2018581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 25.

The square root of 2018581 is about 1420.7677501971. The cubic root of 2018581 is about 126.3810794264.

The spelling of 2018581 in words is "two million, eighteen thousand, five hundred eighty-one".