2103561 has 12 divisors (see below), whose sum is σ = 3121092. Its totient is φ = 1364256.

The previous prime is 2103553. The next prime is 2103583. The reversal of 2103561 is 1653012.

2103561 is a `hidden beast` number, since 2 + 103 + 561 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1550025 + 553536 = 1245^2 + 744^2 .

It is not a de Polignac number, because 2103561 - 2³ = 2103553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2103961) 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, 2826 + ... + 3491.

It is an arithmetic number, because the mean of its divisors is an integer number (260091).

2^2103561 is an apocalyptic number.

It is an amenable number.

2103561 is a deficient number, since it is larger than the sum of its proper divisors (1017531).

2103561 is a wasteful number, since it uses less digits than its factorization.

2103561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6360 (or 6357 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 2103561 is about 1450.3658159237. The cubic root of 2103561 is about 128.1302588363.

Adding to 2103561 its reverse (1653012), we get a palindrome (3756573).

The spelling of 2103561 in words is "two million, one hundred three thousand, five hundred sixty-one".