2101521 has 16 divisors (see below), whose sum is σ = 2949120. Its totient is φ = 1329360.

The previous prime is 2101513. The next prime is 2101531. The reversal of 2101521 is 1251012.

It is not a de Polignac number, because 2101521 - 2³ = 2101513 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2101497 and 2101506.

It is not an unprimeable number, because it can be changed into a prime (2101501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5296 + ... + 5678.

It is an arithmetic number, because the mean of its divisors is an integer number (184320).

2^2101521 is an apocalyptic number.

It is an amenable number.

2101521 is a deficient number, since it is larger than the sum of its proper divisors (847599).

2101521 is a wasteful number, since it uses less digits than its factorization.

2101521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476.

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 2101521 is about 1449.6623744859. The cubic root of 2101521 is about 128.0888258774.

Adding to 2101521 its reverse (1251012), we get a palindrome (3352533).

The spelling of 2101521 in words is "two million, one hundred one thousand, five hundred twenty-one".