2113521 has 4 divisors (see below), whose sum is σ = 2818032. Its totient is φ = 1409012.

The previous prime is 2113513. The next prime is 2113523. The reversal of 2113521 is 1253112.

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 a cyclic number.

It is not a de Polignac number, because 2113521 - 2³ = 2113513 is a prime.

It is a D-number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2113521.

It is not an unprimeable number, because it can be changed into a prime (2113523) 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, 352251 + ... + 352256.

It is an arithmetic number, because the mean of its divisors is an integer number (704508).

2^2113521 is an apocalyptic number.

It is an amenable number.

2113521 is a deficient number, since it is larger than the sum of its proper divisors (704511).

2113521 is an equidigital number, since it uses as much as digits as its factorization.

2113521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704510.

The product of its digits is 60, while the sum is 15.

The square root of 2113521 is about 1453.7953776237. The cubic root of 2113521 is about 128.3321654285.

Adding to 2113521 its reverse (1253112), we get a palindrome (3366633).

The spelling of 2113521 in words is "two million, one hundred thirteen thousand, five hundred twenty-one".