2581181 has 2 divisors, whose sum is σ = 2581182. Its totient is φ = 2581180.

The previous prime is 2581177. The next prime is 2581211. The reversal of 2581181 is 1811852.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2464900 + 116281 = 1570^2 + 341^2 .

It is a cyclic number.

It is not a de Polignac number, because 2581181 - 2² = 2581177 is a prime.

It is a super-2 number, since 2×2581181² = 13324990709522, which contains 22 as substring.

It is a Chen prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 2581181.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2581121) 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 as a sum of consecutive naturals, namely, 1290590 + 1290591.

It is an arithmetic number, because the mean of its divisors is an integer number (1290591).

2^2581181 is an apocalyptic number.

It is an amenable number.

2581181 is a deficient number, since it is larger than the sum of its proper divisors (1).

2581181 is an equidigital number, since it uses as much as digits as its factorization.

2581181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 640, while the sum is 26.

The square root of 2581181 is about 1606.6054276019. The cubic root of 2581181 is about 137.1743212261.

The spelling of 2581181 in words is "two million, five hundred eighty-one thousand, one hundred eighty-one".