2749561 has 4 divisors (see below), whose sum is σ = 2753892. Its totient is φ = 2745232.

The previous prime is 2749543. The next prime is 2749567. The reversal of 2749561 is 1659472.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 250000 + 2499561 = 500^2 + 1581^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2749561 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2749567) 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 in 3 ways as a sum of consecutive naturals, for example, 1006 + ... + 2551.

It is an arithmetic number, because the mean of its divisors is an integer number (688473).

2^2749561 is an apocalyptic number.

It is an amenable number.

2749561 is a deficient number, since it is larger than the sum of its proper divisors (4331).

2749561 is an equidigital number, since it uses as much as digits as its factorization.

2749561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4330.

The product of its digits is 15120, while the sum is 34.

The square root of 2749561 is about 1658.1800264145. The cubic root of 2749561 is about 140.0945110132.

It can be divided in two parts, 27495 and 61, that added together give a square (27556 = 166²).

The spelling of 2749561 in words is "two million, seven hundred forty-nine thousand, five hundred sixty-one".