2981581 has 2 divisors, whose sum is σ = 2981582. Its totient is φ = 2981580.

The previous prime is 2981569. The next prime is 2981597. The reversal of 2981581 is 1851892.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2722500 + 259081 = 1650^2 + 509^2 .

It is a cyclic number.

It is not a de Polignac number, because 2981581 - 2⁷ = 2981453 is a prime.

It is a super-2 number, since 2×2981581² = 17779650519122, which contains 22 as substring.

It is an Ulam number.

It is a nialpdrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2981501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1490790 + 1490791.

It is an arithmetic number, because the mean of its divisors is an integer number (1490791).

2^2981581 is an apocalyptic number.

It is an amenable number.

2981581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2981581 is an equidigital number, since it uses as much as digits as its factorization.

2981581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 34.

The square root of 2981581 is about 1726.7255137977. The cubic root of 2981581 is about 143.9291865045.

The spelling of 2981581 in words is "two million, nine hundred eighty-one thousand, five hundred eighty-one".