2681521 has 2 divisors, whose sum is σ = 2681522. Its totient is φ = 2681520.

The previous prime is 2681507. The next prime is 2681533. The reversal of 2681521 is 1251862.

2681521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2624400 + 57121 = 1620^2 + 239^2 .

It is a cyclic number.

It is not a de Polignac number, because 2681521 - 2⁹ = 2681009 is a prime.

It is an Ulam number.

2681521 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (2681561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1340760 + 1340761.

It is an arithmetic number, because the mean of its divisors is an integer number (1340761).

2^2681521 is an apocalyptic number.

It is an amenable number.

2681521 is a deficient number, since it is larger than the sum of its proper divisors (1).

2681521 is an equidigital number, since it uses as much as digits as its factorization.

2681521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 960, while the sum is 25.

The square root of 2681521 is about 1637.5350377931. The cubic root of 2681521 is about 138.9292637345.

The spelling of 2681521 in words is "two million, six hundred eighty-one thousand, five hundred twenty-one".