2105521 has 6 divisors (see below), whose sum is σ = 2314466. Its totient is φ = 1914000.

The previous prime is 2105513. The next prime is 2105549. The reversal of 2105521 is 1255012.

It can be written as a sum of positive squares in only one way, i.e., 1860496 + 245025 = 1364^2 + 495^2 .

It is not a de Polignac number, because 2105521 - 2³ = 2105513 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2105495 and 2105504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2105591) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8580 + ... + 8821.

2^2105521 is an apocalyptic number.

It is an amenable number.

2105521 is a deficient number, since it is larger than the sum of its proper divisors (208945).

2105521 is a wasteful number, since it uses less digits than its factorization.

2105521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17423 (or 17412 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 2105521 is about 1451.0413502034. The cubic root of 2105521 is about 128.1700417487.

The spelling of 2105521 in words is "two million, one hundred five thousand, five hundred twenty-one".