3111561 has 16 divisors (see below), whose sum is σ = 4881600. Its totient is φ = 1952064.

The previous prime is 3111539. The next prime is 3111569. The reversal of 3111561 is 1651113.

It is not a de Polignac number, because 3111561 - 2¹⁰ = 3110537 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3111569) 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 15 ways as a sum of consecutive naturals, for example, 2931 + ... + 3848.

It is an arithmetic number, because the mean of its divisors is an integer number (305100).

Almost surely, 2^3111561 is an apocalyptic number.

It is an amenable number.

3111561 is a deficient number, since it is larger than the sum of its proper divisors (1770039).

3111561 is a wasteful number, since it uses less digits than its factorization.

3111561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6805 (or 6799 counting only the distinct ones).

The product of its digits is 90, while the sum is 18.

The square root of 3111561 is about 1763.9617342788. The cubic root of 3111561 is about 145.9910077654.

Adding to 3111561 its reverse (1651113), we get a palindrome (4762674).

The spelling of 3111561 in words is "three million, one hundred eleven thousand, five hundred sixty-one".