2981561 has 12 divisors (see below), whose sum is σ = 3362772. Its totient is φ = 2640000.

The previous prime is 2981551. The next prime is 2981569. The reversal of 2981561 is 1651892.

It can be written as a sum of positive squares in 2 ways, for example, as 1210000 + 1771561 = 1100^2 + 1331^2 .

It is not a de Polignac number, because 2981561 - 2¹⁴ = 2965177 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2981569) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4661 + ... + 5261.

It is an arithmetic number, because the mean of its divisors is an integer number (280231).

2^2981561 is an apocalyptic number.

It is an amenable number.

2981561 is a deficient number, since it is larger than the sum of its proper divisors (381211).

2981561 is a wasteful number, since it uses less digits than its factorization.

2981561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 664 (or 653 counting only the distinct ones).

The product of its digits is 4320, while the sum is 32.

The square root of 2981561 is about 1726.7197224796. The cubic root of 2981561 is about 143.9288646852.

The spelling of 2981561 in words is "two million, nine hundred eighty-one thousand, five hundred sixty-one".