2881621 has 2 divisors, whose sum is σ = 2881622. Its totient is φ = 2881620.

The previous prime is 2881591. The next prime is 2881639. The reversal of 2881621 is 1261882.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2852721 + 28900 = 1689^2 + 170^2 .

It is a cyclic number.

It is not a de Polignac number, because 2881621 - 2⁵ = 2881589 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2881621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2884621) 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, 1440810 + 1440811.

It is an arithmetic number, because the mean of its divisors is an integer number (1440811).

2^2881621 is an apocalyptic number.

It is an amenable number.

2881621 is a deficient number, since it is larger than the sum of its proper divisors (1).

2881621 is an equidigital number, since it uses as much as digits as its factorization.

2881621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1536, while the sum is 28.

The square root of 2881621 is about 1697.5337993690. The cubic root of 2881621 is about 142.3024203400.

The spelling of 2881621 in words is "two million, eight hundred eighty-one thousand, six hundred twenty-one".