2011521 has 4 divisors (see below), whose sum is σ = 2682032. Its totient is φ = 1341012.

The previous prime is 2011517. The next prime is 2011531. The reversal of 2011521 is 1251102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2011521 - 2² = 2011517 is a prime.

It is a D-number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2011497 and 2011506.

It is not an unprimeable number, because it can be changed into a prime (2011531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 335251 + ... + 335256.

It is an arithmetic number, because the mean of its divisors is an integer number (670508).

2^2011521 is an apocalyptic number.

It is an amenable number.

2011521 is a deficient number, since it is larger than the sum of its proper divisors (670511).

2011521 is an equidigital number, since it uses as much as digits as its factorization.

2011521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 670510.

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

The square root of 2011521 is about 1418.2810017764. The cubic root of 2011521 is about 126.2335677728.

Adding to 2011521 its reverse (1251102), we get a palindrome (3262623).

The spelling of 2011521 in words is "two million, eleven thousand, five hundred twenty-one".